ci: use ruff for linting

[kiike]

HI again!

Here is a companion PR for the discussion in #812.

It adds linting with ruff, which catches many more style "issues". Along getting rid of many dependencies, it provides faster linting and formatting, which can be pretty cool when used with pre-commit, for instance.

I tried to port some of the excluded rules.

WIP

[alexfikl]

I'm on board with switching to ruff, but probably after we make a release with the current stuff. It's definitely due :grin:

[kiike]

Sure. It can add a lot of new rules, so that will involve picking which ones the project wants. Luckily, it auto-fixes most of the minor issues.

[jghauser]

I'm definitely on board with using ruff. I've been using it on my side for a while and it would be nice to have some way of easily enforcing a nice consistent style :).

[kiike]

Cool! We'll keep this PR on the backburner!