Remove tox, tox-pyenv

tox changes too quickly and we should install it in the consuming
application, while tox-pyenv is no longer maintained and doesn't appear
to be necessary.

Signed-off-by: Stephen Finucane <[email protected]>

Author: stephenfin

Dockerfile

@@ -57,8 +57,7 @@ RUN pyenv install 3.7 && \
             \( -type d -a \( -name test -o -name tests -o -name idle_test \) \) \
             -o \( -type f -a \( -name '*.pyc' -o -name '*.pyo' -o -name '*.a' \) \) \
             -o \( -type f -a -name 'wininst-*.exe' \) \
-        \) -exec rm -rf '{}' +  && \
-    pip install tox tox-pyenv
+        \) -exec rm -rf '{}' +
 
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