Updates the requirements on [orchestra/testbench](https://github.com/…

…orchestral/testbench) to permit the latest version.

<details>
<summary>Release notes</summary>
<p><em>Sourced from <a href="https://github.com/orchestral/testbench/releases">orchestra/testbench's releases</a>.</em></p>
<blockquote>
<h2>v4.13.0</h2>
<h3>Changes</h3>
<ul>
<li>Update minimum support for Testbench Core v4.12.0+. (<a href="https://github.com/orchestral/testbench-core/compare/v4.11.1...v4.12.0">v4.11.1...v4.12.0</a>)</li>
</ul>
<h4>Testbench Changes</h4>
<h5>Changes</h5>
<ul>
<li>Bump <code>mockery/mockery</code> to <code>v1.3.2</code> and above.</li>
<li>Opt to use <code>method_exists()</code> to detect support for <code>parseTestMethodAnnotations()</code> under <code>HandlesDatabases</code> and <code>HandlesRoutes</code> trait.</li>
<li>Update <code>Orchestra\Testbench\Bootstrap\LoadConfiguration::getConfigurationFiles()</code> to return <code>Generator</code> instead of array.</li>
</ul>
</blockquote>
</details>
<details>
<summary>Changelog</summary>
<p><em>Sourced from <a href="https://github.com/orchestral/testbench/blob/v4.13.0/CHANGELOG-4.x.md">orchestra/testbench's changelog</a>.</em></p>
<blockquote>
<h2>4.13.0</h2>
<p>Release: 2020-12-15</p>
<h3>Changes</h3>
<ul>
<li>Update minimum support for Testbench Core v4.12.0+. (<a href="https://github.com/orchestral/testbench-core/compare/v4.11.1...v4.12.0">v4.11.1...v4.12.0</a>)</li>
</ul>
<h4>Testbench Changes</h4>
<h5>Changes</h5>
<ul>
<li>Bump <code>mockery/mockery</code> to <code>v1.3.2</code> and above.</li>
<li>Opt to use <code>method_exists()</code> to detect support for <code>parseTestMethodAnnotations()</code> under <code>HandlesDatabases</code> and <code>HandlesRoutes</code> trait.</li>
<li>Update <code>Orchestra\Testbench\Bootstrap\LoadConfiguration::getConfigurationFiles()</code> to return <code>Generator</code> instead of array.</li>
</ul>
<h2>4.12.2</h2>
<p>Released: 2020-12-10</p>
<h3>Changes</h3>
<ul>
<li>Update minimum support for Testbench Core v4.11.1+. (<a href="https://github.com/orchestral/testbench-core/compare/v4.11.0...v4.11.1">v4.11.0...v4.11.1</a>)</li>
</ul>
<h4>Testbench Changes</h4>
<h5>Fixes</h5>
<ul>
<li>Removed <code>abstract</code> method <code>parseTestMethodAnnotations()</code> to revert breaking changes.</li>
</ul>
<h2>4.12.1</h2>
<p>Released: 2020-12-09</p>
<h3>Fixes</h3>
<ul>
<li>Fixes Testbench Core dependencies.</li>
</ul>
<h2>4.12.0</h2>
<p>Released: 2020-12-09</p>
<h3>Changes</h3>
<ul>
<li>Update minimum support for Testbench Core v4.11.0+. (<a href="https://github.com/orchestral/testbench-core/compare/v4.10.0...v4.11.0">v4.10.0...v4.11.0</a>)</li>
</ul>
<h4>Testbench Changes</h4>
<h5>Added</h5>
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</blockquote>
<p>... (truncated)</p>
</details>
<details>
<summary>Commits</summary>
<ul>
<li>See full diff in <a href="https://github.com/orchestral/testbench/commits/v4.13.0">compare view</a></li>
</ul>
</details>
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</details>

composer.json

@@ -35,7 +35,7 @@
   },
   "require-dev": {
     "umbrellio/code-style-php": "^1.0",
-    "orchestra/testbench": "^3.5|^6.0",
+    "orchestra/testbench": "^3.5|^6.0|^4.0",
     "php-coveralls/php-coveralls": "^2.1",
     "codeception/codeception": "^3.0|^4.0"
   },