improvement: Bump black to >=23.1.0

[mcintel]

Along with this, also needed to bump pydoc-markdown. And for good measure, added docs/_site to .gitignore so slap run docs:build won't show a bunch of new files to add.

[mcintel]

@NiklasRosenstein I didn't totally understand how to add the .changelog/_unreleased.log. If you can give me a tip, I'll be more than happy to add it.

[NiklasRosenstein]

Thanks for the contribution @mcintel! You can mimic the same format after generating a fresh uuid for the id field, or install slap-cli with Pip(x) and use slap changelog add -t improvement -d 'Bump black to `>=23.1.0`'

[mcintel]

@NiklasRosenstein Ah, thanks for the info. I see that the verify failed. I'll try to repro and fix.

Thanks for this tool! It's super rad! 😁

[NiklasRosenstein]

Glad you like it ❤️

Black needs to be pinned to a major version as the next major version will most likely have breaking formatting changes; as demonstrated by the Python 3.7 tests (which get a 23.x version and all the other tests get the latest 24.x version).

One workaround would be to run Black for linting in this project separately from the runtime dependency; but I would say we can just drop the 3.7 support all together since that Python version is no longer supported.