[MAINTENANCE] Add lint step to CI

[tyler-hoffman]

Looks like in 026cb66 we switched from the linter to the formatter. Now we have both 🎉

We previously had ruff formatter on, but not linting. This adds linting, and opts into 2 categories or rules:

• flake8 type checking: https://docs.astral.sh/ruff/rules/#flake8-type-checking-tc
• isort: https://docs.astral.sh/ruff/rules/#isort-i

[joshua-stauffer]

thank you!