Actually Black format everything

[MicahGale]

Description

This is a follow-on to #3222 that actually formats everything with black.

Proposed way to merge.

1. Review and approve Laid out infrastructure for switching to black formatting all code. #3222.
2. Run black locally on develop and then compare with this PR. I think this is the only way to verify nothing was snuck in with so many changes.
3. This will lead to a lot of merge conflicts for all open PRs. I would recommend that those with open PRs:
   1. Run black against their branch and commit.
   2. Merge in develop. This should eliminate almost all merge conflicts.

Fixes #2002 (actually implement.)

Checklist

• I have performed a self-review of my own code
• I have run clang-format (version 15) on any C++ source files (if applicable)
• I have followed the style guidelines for Python source files (if applicable)
• I have made corresponding changes to the documentation (if applicable)
• I have added tests that prove my fix is effective or that my feature works (if applicable)

[lewisgross1296]

Wondering if this PR got lost over the holidays and new year. Is anyone opposed to this or does any of the leadership team have a strong opinion one way or the other? I do support black formatting, as I'm finding when I try to edit source code for a different PR, my black formatter is formatting previously merged code. Apparently black has a unique formatting choice (that can be tweaked with certain settings e.g. max line length), which is desirable to me to more easily prevent unwanted diffs in my PRs.

I can live with changing my formatter settings for openmc and manually formatting source code additions, but I think it would be cool to unify the formatting. We can always use the # fmt: off and #f mt: on if there's any parts that get less readable from the auto format.