Fix wrong base tag used for deployment and displayed in About dialog

[Holzhaus]

By default, git describe shows the number of commits from the latest
tag in the git history. In our case we don't want that, because this can
cause problems:

        2.4-alpha              Expected: 2.4-alpha-N-abcdef123
main ---+X---------------+---> Actual: 2.3.0-M-abcdef456
         \              /
          X------------X--->
         2.3-beta     2.3.0

Hence, we need to add the --first-parent flag to git describe, so that
it only follows the first parent of a merge and does not pull in tags
from another branch.

Fixes mixxxdj/website#248.

See the issue for details: mixxxdj/website#248

[Holzhaus]

Note that this is based on the 2.3 branch and we might consider merging it into 2.3 instead of main to prevent being bitten by this when releasing 2.3.1 or something.

[uklotzde]

Works locally. Please verify, confirm, and merge.

[daschuer]

I can confirm that this issue is fixed. However the branch is displayed wrong (HEAD) in the github builds.
I think this should be git-describe-first-parent or the PR number or something that you can find the source of this binary later.

[daschuer]

Do you like to fix it here or shall we track this as bug?

[Be-ing]

If this introduces a regression in the stable branch, that should be fixed in the same PR.

[Holzhaus]

Is it actually a regression? We should check if this was also the case before this PR.

[daschuer]

I am pretty sure that this is not a regression.

[Holzhaus]

I am pretty sure that this is not a regression.

Yes, looks like this problem was present before: https://github.com/mixxxdj/mixxx/runs/3013968489#step:20:387 (build log from unrelated qml library PR)

I think the missing branch name comes from github creating a merge commit without fetching branch names. But this should be taken care of in another PR.

[daschuer]

I have filed a bug: https://bugs.launchpad.net/mixxx/+bug/1934976

[daschuer]

Thank you for the fix.