Improve ListenBrainz error handling and simplify playlist handling

[arsaboo]

Description

Fixes #5459

To Do

• Changelog. (Add an entry to docs/changelog.rst to the bottom of one of the lists near the top of the document.)
• Tests. (Very much encouraged but not strictly required.)

[snejus]

I commented under the change that is required to fix #5459.

Could you by any chance submit the rest of the changes in a separate PR as they seem to be a more general refactor?

Also, I suspect you are using black to do auto formatting - note that the max line length is configured as 80 across the project.

This should have been caught by CI, but now I see that ruff only shouts for line lengths longer than 88.

[arsaboo]

@snejus Made the changes. It looks like the check is failing for unrelated reasons.

[snejus]

Thank you! The fix looks fine to me.

Could you by any chance submit the rest of the changes in a separate PR as they seem to be a more general refactor?

Above I asked to only keep the fix to the issue in this PR. That's because this plugin is not tested, so there's no way to verify that a refactor did not introduce any unwanted effects.

If you do want to keep the rest of the changes here, would you be happy adding some tests?

[arsaboo]

Tests are not my strong suit unfortunately...

The current version is broken anyways, so I don't think we can be worse off. I'm here in case there are any issues that come up. I use this plugin regularly, so trust me I'll be the first to identify an issue 😜

[bal-e]

This is a nice and simple little change, thanks @arsaboo!

[snejus]

Okay, let's go then!