* Install our core dependencies for mypy in azure
To match local setups and tox.
* Use "system" mypy in pre-commit instead of the "real" mypy hook
The results of mypy depend on what is installed. And the mypy hook
runs in a virtualenv of its own, meaning we'd need to install and
maintain another set of our dependencies there... no. Use the "system"
one and reuse the environment that is set up anyway already instead.
* Reintroduce needed ruamel.yaml type ignore
This ignore is required when ruamel.yaml is installed, and we want it
to be as it's part of the core dependency set.
* Upgrade pydocstyle to 4.0.0 and flake8-docstrings to 1.3.1
http://www.pydocstyle.org/en/4.0.0/release_notes.html#july-6th-2019
* Address pydocstyle D413's
* tox: do not run pydocstyle
Does not seem to add any value over flake8-docstrings (and would have
needed a D202 exclusion).
* Revert "Add some debugging to azure mypy job (#25632)"
This reverts commit 767b8e9f25.
No longer needed.
* Install setup.py dependencies for mypy in Azure
For better coverage, and to match what tox does.