sourcebuild broken (version detection)

[mara004]

Checklist

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Reason for Generic issue (keyword/topic)

pdfium build script

Description

See https://github.com/pypdfium2-team/pypdfium2/actions/runs/6818844030
git describe --all fails to detect the latest version and returns main instead, although the version is visible in git log.
Tried various other forms of git describe but none of them seemed to work.

The odd thing is that it worked previously, see e.g. https://github.com/pypdfium2-team/pypdfium2/actions/runs/6799778599

Note that removing --shallow --no-history and adding --with_branch_heads does not fix the issue (see e10f667).
I guess we might have to traverse the log and compare against ls-remote on our own or something.
git just doesn't seem to play well with google's awkward heads...