Simplify lints

[janhohenheim]

Fixes #639
Additionally removes lint for ul list style.

I'm relaxing our lints massively because I want to streamline the process for potential contributors by reducing as much friction as possible. If the current editors since the revival find the lints too relaxed, I'm very open to changing them in the next release cycle.

[17cupsofcoffee]

Very much in favour of this - it's the style of the output we care about, not so much the Markdown itself. As long as the submission renders nicely and is easily reviewable/editable, I don't think there's much value in chasing people over line lengths or list styles tbh.

[Keavon]

I'll just drop a comment to mention that any line length limit (like 160 now) still means contributors can't just type text and will still have to submit a PR, learn that it fails CI, investigate, make changes to break the text across lines, and re-submit the PR at least once more. Doubling the limit makes it slightly less annoying but doesn't fix that frustrating and (for new contributors) surprising limitation. Make of that what you will, but that's just an explanation of my view.

[janhohenheim]

@Keavon good point. I decided to leave in a limit as a compromise since #639 shows that editors generally really want a character limit. If I see many contributors running into this, I'll open a PR removing the limit altogether.

[janhohenheim]

Got a follow-up at #1480
@17cupsofcoffee could you check it out when you have time?