Fix issue during the parsing of "badbins"

[AbstractUmbra]

Description

This PR corrects the behaviour which was added to parse content from "badbins", the likes of pastebin and hastebin and send them to mystb.in.
The problem is that previous iterations of mystbin returns a "notice" field in the response, we used to use that to notice the pasting user of their notice. This is no longer the case.

The code was previously updated to account for this, but further in the on_message listener we attempt to unpack the return of the function which previously returned a tuple[str, str], but now only returns str.

Pyright did not catch this, believing that foo, bar = "baz" to be valid in this case, which it was not.

This corrects that, as well as bad code smells.

EDIT: Our ruff action isn't version bound, so I've had to update, run and correct code around ruff. I can split this into a separate PR if necessary.

Checklist

• If code changes were made then they have been tested.
  • I have updated the documentation to reflect the changes.
  • I have updated the changelog with a quick recap of my changes.
• This PR fixes an issue.
• This PR adds something new (e.g. new method or parameters).
• This PR is a breaking change (e.g. methods or parameters removed/renamed)
• This PR is not a code change (e.g. documentation, README, ...)
• I have read and agree to the Developer Certificate of Origin for this contribution