chore(deps-dev): bump black from 21.11b1 to 21.12b0 (aws-powertools#872)

Bumps [black](https://github.com/psf/black) from 21.11b1 to 21.12b0.
<details>
<summary>Release notes</summary>
<p><em>Sourced from <a href="https://github.com/psf/black/releases">black's releases</a>.</em></p>
<blockquote>
<h2>21.12b0</h2>
<h3><em>Black</em></h3>
<ul>
<li>Fix determination of f-string expression spans (<a href="https://github-redirect.dependabot.com/psf/black/issues/2654">#2654</a>)</li>
<li>Fix bad formatting of error messages about EOF in multi-line statements (<a href="https://github-redirect.dependabot.com/psf/black/issues/2343">#2343</a>)</li>
<li>Functions and classes in blocks now have more consistent surrounding spacing (<a href="https://github-redirect.dependabot.com/psf/black/issues/2472">#2472</a>)</li>
</ul>
<h4>Jupyter Notebook support</h4>
<ul>
<li>Cell magics are now only processed if they are known Python cell magics. Earlier, all cell magics were tokenized, leading to possible indentation errors e.g. with <code>%%writefile</code>. (<a href="https://github-redirect.dependabot.com/psf/black/issues/2630">#2630</a>)</li>
<li>Fix assignment to environment variables in Jupyter Notebooks (<a href="https://github-redirect.dependabot.com/psf/black/issues/2642">#2642</a>)</li>
</ul>
<h4>Python 3.10 support</h4>
<ul>
<li>Point users to using <code>--target-version py310</code> if we detect 3.10-only syntax (<a href="https://github-redirect.dependabot.com/psf/black/issues/2668">#2668</a>)</li>
<li>Fix <code>match</code> statements with open sequence subjects, like <code>match a, b:</code> or <code>match a, *b:</code> (<a href="https://github-redirect.dependabot.com/psf/black/issues/2639">#2639</a>) (<a href="https://github-redirect.dependabot.com/psf/black/issues/2659">#2659</a>)</li>
<li>Fix <code>match</code>/<code>case</code> statements that contain <code>match</code>/<code>case</code> soft keywords multiple times, like <code>match re.match()</code> (<a href="https://github-redirect.dependabot.com/psf/black/issues/2661">#2661</a>)</li>
<li>Fix <code>case</code> statements with an inline body (<a href="https://github-redirect.dependabot.com/psf/black/issues/2665">#2665</a>)</li>
<li>Fix styling of starred expressions inside <code>match</code> subject (<a href="https://github-redirect.dependabot.com/psf/black/issues/2667">#2667</a>)</li>
<li>Fix parser error location on invalid syntax in a <code>match</code> statement (<a href="https://github-redirect.dependabot.com/psf/black/issues/2649">#2649</a>)</li>
<li>Fix Python 3.10 support on platforms without ProcessPoolExecutor (<a href="https://github-redirect.dependabot.com/psf/black/issues/2631">#2631</a>)</li>
<li>Improve parsing performance on code that uses <code>match</code> under <code>--target-version py310</code> up to ~50% (<a href="https://github-redirect.dependabot.com/psf/black/issues/2670">#2670</a>)</li>
</ul>
<h3>Packaging</h3>
<ul>
<li>Remove dependency on <code>regex</code> (<a href="https://github-redirect.dependabot.com/psf/black/issues/2644">#2644</a>) (<a href="https://github-redirect.dependabot.com/psf/black/issues/2663">#2663</a>)</li>
</ul>
<hr />
<h4>Thank you!</h4>
<ul>
<li><a href="https://github.com/isidentical"><code>@​isidentical</code></a> for the polishing up 3.10 syntax support (which they contributed in the first place!)</li>
<li><a href="https://github.com/MarcoGorelli"><code>@​MarcoGorelli</code></a> for their ever-continuing work on Black's jupyter support</li>
<li><a href="https://github.com/jalaziz"><code>@​jalaziz</code></a> for cleaning up our Pyinstaller CD workflow</li>
<li><a href="https://github.com/hauntsaninja"><code>@​hauntsaninja</code></a> for helping us drop the <code>regex</code> dependency</li>
</ul>
<p>And also congrats to first contributors!</p>
<ul>
<li><a href="https://github.com/MatthewScholefield"><code>@​MatthewScholefield</code></a> made their first contribution in <a href="https://github-redirect.dependabot.com/psf/black/pull/2631">psf/black#2631</a></li>
<li><a href="https://github.com/AshIsbitt"><code>@​AshIsbitt</code></a> made their first contribution in <a href="https://github-redirect.dependabot.com/psf/black/pull/2632">psf/black#2632</a></li>
<li><a href="https://github.com/kalbasit"><code>@​kalbasit</code></a> made their first contribution in <a href="https://github-redirect.dependabot.com/psf/black/pull/2638">psf/black#2638</a></li>
<li><a href="https://github.com/danieleades"><code>@​danieleades</code></a> made their first contribution in <a href="https://github-redirect.dependabot.com/psf/black/pull/2653">psf/black#2653</a></li>
<li><a href="https://github.com/danielsparing"><code>@​danielsparing</code></a> made their first contribution in <a href="https://github-redirect.dependabot.com/psf/black/pull/2630">psf/black#2630</a></li>
<li><a href="https://github.com/tanvimoharir"><code>@​tanvimoharir</code></a> made their first contribution in <a href="https://github-redirect.dependabot.com/psf/black/pull/2343">psf/black#2343</a></li>
</ul>
</blockquote>
</details>
<details>
<summary>Changelog</summary>
<p><em>Sourced from <a href="https://github.com/psf/black/blob/main/CHANGES.md">black's changelog</a>.</em></p>
<blockquote>
<h2>21.12b0</h2>
<h3><em>Black</em></h3>
<ul>
<li>Fix determination of f-string expression spans (<a href="https://github-redirect.dependabot.com/psf/black/issues/2654">#2654</a>)</li>
<li>Fix bad formatting of error messages about EOF in multi-line statements (<a href="https://github-redirect.dependabot.com/psf/black/issues/2343">#2343</a>)</li>
<li>Functions and classes in blocks now have more consistent surrounding spacing (<a href="https://github-redirect.dependabot.com/psf/black/issues/2472">#2472</a>)</li>
</ul>
<h4>Jupyter Notebook support</h4>
<ul>
<li>Cell magics are now only processed if they are known Python cell magics. Earlier, all
cell magics were tokenized, leading to possible indentation errors e.g. with
<code>%%writefile</code>. (<a href="https://github-redirect.dependabot.com/psf/black/issues/2630">#2630</a>)</li>
<li>Fix assignment to environment variables in Jupyter Notebooks (<a href="https://github-redirect.dependabot.com/psf/black/issues/2642">#2642</a>)</li>
</ul>
<h4>Python 3.10 support</h4>
<ul>
<li>Point users to using <code>--target-version py310</code> if we detect 3.10-only syntax (<a href="https://github-redirect.dependabot.com/psf/black/issues/2668">#2668</a>)</li>
<li>Fix <code>match</code> statements with open sequence subjects, like <code>match a, b:</code> or
<code>match a, *b:</code> (<a href="https://github-redirect.dependabot.com/psf/black/issues/2639">#2639</a>) (<a href="https://github-redirect.dependabot.com/psf/black/issues/2659">#2659</a>)</li>
<li>Fix <code>match</code>/<code>case</code> statements that contain <code>match</code>/<code>case</code> soft keywords multiple
times, like <code>match re.match()</code> (<a href="https://github-redirect.dependabot.com/psf/black/issues/2661">#2661</a>)</li>
<li>Fix <code>case</code> statements with an inline body (<a href="https://github-redirect.dependabot.com/psf/black/issues/2665">#2665</a>)</li>
<li>Fix styling of starred expressions inside <code>match</code> subject (<a href="https://github-redirect.dependabot.com/psf/black/issues/2667">#2667</a>)</li>
<li>Fix parser error location on invalid syntax in a <code>match</code> statement (<a href="https://github-redirect.dependabot.com/psf/black/issues/2649">#2649</a>)</li>
<li>Fix Python 3.10 support on platforms without ProcessPoolExecutor (<a href="https://github-redirect.dependabot.com/psf/black/issues/2631">#2631</a>)</li>
<li>Improve parsing performance on code that uses <code>match</code> under <code>--target-version py310</code>
up to ~50% (<a href="https://github-redirect.dependabot.com/psf/black/issues/2670">#2670</a>)</li>
</ul>
<h3>Packaging</h3>
<ul>
<li>Remove dependency on <code>regex</code> (<a href="https://github-redirect.dependabot.com/psf/black/issues/2644">#2644</a>) (<a href="https://github-redirect.dependabot.com/psf/black/issues/2663">#2663</a>)</li>
</ul>
</blockquote>
</details>
<details>
<summary>Commits</summary>
<ul>
<li>See full diff in <a href="https://github.com/psf/black/commits">compare view</a></li>
</ul>
</details>
<br />


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pyproject.toml

@@ -31,7 +31,7 @@ email-validator = {version = "*", optional = true }
 [tool.poetry.dev-dependencies]
 coverage = {extras = ["toml"], version = "^6.2"}
 pytest = "^6.2.5"
-black = "^21.11b1"
+black = "^21.12b0"
 flake8 = "^4.0.1"
 flake8-black = "^0.2.3"
 flake8-builtins = "^1.5.3"