Use HTTPS for MusicBrainz URLs

[Rigo-V]

Since these redirect to HTTPS anyway, why not do it explicitly and maybe prevent some machine in the middle attacks.

[phw]

Thanks. I had previously refrained from this change as it is a potential API breaking change. But probably we can risk that. The only way I see this breaking someones code is if that code would specifically check or parse the generated URLs in a way that doesn't deal with the protocol change. But we can prominently point this change out in the release notes. It's not like libdiscid is constantly changing anyway :)

In any case, the tests need to be adjusted.

[Rigo-V]

I see. I only found "http://" in test_put.c, and updated it to match.

[phw]

Thanks, LGTM

[phw]

@Rigo-V I'm actually considering reverting this change. I found several usages like https://github.com/njh/perl-musicbrainz-discid/blob/main/t/10discid.t#L34 . There might be more such reliance on the URL in application code.

I updated the language bindings I personally control to not care about http / https in tests. Affected were hare-discid, rust-discid and go-discid.

But given that this is technically a breaking change we might want to avoid releasing this with the next release. Maybe announce that this will change in a future release. Or we put it behind a build flag maybe?

Also thinking about it we should likely skip this change for the web service URL completely. This method was deprecated a long time ago an the URL it returns is useless. It is only kept for backward compatibility, and breaking the URL in it seems pointless.