discogs: Fix discogs_albumid extraction

[JOJ0]

Description

• Fixes discogs: discogs_albumid is always 0 #4225
• Discogs changed their release URL format. This fixes the albumid extraction by using an improved extraction method.

To Do

• Documentation.
• Changelog.
• Tests.

[sampsyo]

Looks good overall, except that a test seems to be failing.

Also, just to check: is extract_release_id now dead code (never called)? If so, we should remove it. ✨ 🐟

[JOJ0]

Hi @sampsyo
test.test_discogs.DGAlbumInfoTest.test_parse_minimal_release was failing because the test data does not contain a Discogs URL and the regex check wanted to test against a None value.

extract_release_id() had a check whether an URI was passed at all and returned None immediately if not. I added such a check to extract_release_id_regex() as well.

[sampsyo]

Ah, thanks for tracking down the failing test!

I made a silly suggestion within, but maybe the better fix would actually be to just fix the test so it actually includes an ID? (Unless we expect the API to ever return a response without a URL, which I doubt…)

[JOJ0]

Thanks for the review! Added URI to test data, removed sanity check in extract_release_id_regex() and "rebased-in" upstream master.

[sampsyo]

Yay; looks great!!