Correctly parse Guix VCS snapshots as such

[nckx]

This should DTRT if repology/repology-updater#920 (comment) is correct.

Because this was missing there are some buggy ignores scattered across the rule set, which this patch can't fix because the problem isn't technical.

[AMDmi3]

This shouldn't be necessary because there's the same thing (with limited scope though) in the parser:

https://github.com/repology/repology-updater/blob/master/repology/parsers/parsers/guix.py#L63

Are there some cases where it doesn't work right?

[nckx]

Interesting, I wasn't aware of that special case.

Are there some cases where it doesn't work right?

I think so but I don't have a good grasp of the entire Repology codebase.

Here, for example, ‘incorrect’ is, well, incorrect: https://repology.org/project/i7z/versions

[AMDmi3]

What exactly is incorrect in this case?

[nckx]

Yeah, I guess that's my question too. This fork is apparently ‘blessed’ by Repology whilst this one is not? Seems arbitrary, is all.

[AMDmi3]

The incorrect status is in fact caused by an unrelated rule, neither fork is blessed. In fact 0.28 is much older than 0.27.4, but I guess there's no point in giving preference to any of these as both are inactive, so I'd split them into separate projects.

Are there another questionable cases?