Switch from black to ruff for formatting

[xavdid-stripe]

Per discussion, I've swapped from black to ruff for formatting. It's must faster when running make codegen-format:

Before:

558 files reformatted, 104 files left unchanged.
  fmt: OK (13.54=setup[0.05]+cmd[13.48] seconds)
  congratulations :) (13.61 seconds)

after:

474 files reformatted, 188 files left unchanged
  fmt: OK (0.40=setup[0.04]+cmd[0.35] seconds)
  congratulations :) (0.44 seconds)

I separated the PR into 3 main commits:

• tooling changes happened in 9b43579
• mass formatting happened in c46b4b9
• add a rev ignore file in 15c3956 (so I don't get credit for a ton of git-blame lines)

So broadly, a reviewer will mostly want to look at the changes from the first commit. Past that, there are superficial formatting changes, but nothing serious.

[prathmesh-stripe]

Great stuff! Thanks for listing out the separate commits.