feat: improve beatmap api resilience with tenacity & error handling

[tsunyoku]

Describe your changes

Uses tenacity to retry when an exception happens on the web request (connection error or similar), and also explicitly handles when to delete a beatmap when it is fetched for updates so that any server-side error responses that don't actually mean the map got deleted result in an unfairly deleted beatmap.

Related Issues / Projects

Checklist

• [x] I've manually tested my code
• [x] The changes pass pre-commit checks (make lint)
• [x] The changes follow coding style

[tsunyoku]

my local pipenv setup is fucked and won't work (i really wish we didn't have this shit lol) so i cannot add the new tenacity dependency to the Pipfile, will remain in draft until that's sorted

would appreciate if someone could add it for me, pipenv is going to get on my last nerve

[NiceAesth]

I am okay with this so long as tenacity will be used in the future for other endpoints as well.

[NiceAesth]

something's not right with the requirements action and i am not sure i can even see what it is trying to accomplish or why it needs to exist

[tsunyoku]

don't merge until i'm free please

[tsunyoku]

ok should be fine, just wanted to check the changes after mine. will merge it now!