Deprecate bdist_wininst

[hugovk]

Deprecate bdist_wininst

For #1988.

Already deprecated in CPython 3.8's distutils.

The deprecation method, message and tests are modelled on the recent #1764 (deprecate "eggsecutable" scripts).

I had a go at the other bdists mentioned in #1988, but had a hard time with the tests, so here's just one to be getting on with.

Pull Request Checklist

• Changes have tests
• News fragment added in changelog.d. See documentation for details

[jaraco]

Looks good to me.

[pganssle]

@hugovk I made a change to the news fragment and I've changed the test in two ways:

1. Flattened it so that it is no longer part of a class (I've noticed we don't usually do this in other test suites, and this one seems particularly unnecessary).
2. Added the assertion that the original bdist_wininst.run command is invoked as a sanity check.

Let me know if you disagree with these changes, otherwise I'll go ahead and squash my fixup commits into your commits and merge.

[hugovk]

Thanks, both look good!

Do you use some tool for fixing up (I noticed the "fixup! XXX" comments), or just vanilla Git?

[pganssle]

Do you use some tool for fixing up (I noticed the "fixup! XXX" comments), or just vanilla Git?

This is vanilla git, you can use git commit --fixup to mark a commit as a fixup for another commit, and then git rebase --autosquash to automatically squash the fixups into the relevant commits. Here's an article I found on it: https://thoughtbot.com/blog/autosquashing-git-commits

There is a fancy tool that I've been starting to use lately (I got hooked on it when using hg at work), called git-absorb: https://github.com/tummychow/git-absorb

This will automatically determine what parts of whatever you've staged belongs with what commits and create fixup commits for it. Very handy for my workflow.