Enable Ruff RET (flake8-return)

[Avasam]

Ref #13295
https://docs.astral.sh/ruff/rules/#flake8-return-ret

Everything is autofixable

superfluous-else-* (RET505-RET508)'s "make the code more readable" is arguable if you find the else keyword to be helpful to your flow comprehension.
I like its reduced nesting for early conditional guards, but it incidentally catches more than that. Maybe if it could be configured to not apply to single statements ? (astral-sh/ruff#15167)

I find the rest of the RET rules to be good sanity checks.

[JelleZijlstra]

I don't find these to be improvements.

[Avasam]

I don't find these to be improvements.

Just to be clear, are you talking about the changes caused by RET505-RET508 (which I agree, shouldn't be enforced, I just disabled them, e37aa4e (#13323) can be looked at to see the difference) or the entire ruleset ?

[AlexWaygood]

Hmmm... I think I'm -1 on this whole category, actually. These all seem like pretty pedantic stylistic lints that sometimes hurt readability, and usually don't significantly improve readability. (In the rare occasions where there is a significant improvement in readability, I think we'd probably just flag it in code review.)

I think overall this category would be likely just to cause us irritation rather than actually help us, so I think I'd prefer to leave these disabled

[Avasam]

Let's close this one and leave it to reviews.