Move deviations from formatter README to documentation (#10444)

## Summary

#10151 documented the deviations between Ruff and Black with the new
2024 style guide in the `ruff-python-formatter/README.md`. However,
that's not the documentation shown
on the website when navigating to [intentional
deviations](https://docs.astral.sh/ruff/formatter/black/).

This PR streamlines the `ruff-python-formatter/README.md` and links to
the documentation on the website instead of repeating the same content.
The PR also makes the 2024 style guide deviations available on the
website documentation.

## Test Plan

I built the documentation locally and verified that the 2024 style guide
known deviations are now shown on the website.