`git rev-parse HEAD` returns strange rev

[tmnd1991]

I'm running GitHub Actions in a PR (agile-lab-dev/whitefox#124).
The output of git rev-parse HEAD on the github action step (https://github.com/agile-lab-dev/whitefox/actions/runs/6693238754/job/18183970736?pr=124#step:6:121) is different from the commit sha (agile-lab-dev/whitefox@a867be0) that triggered the build and the one I get locally. Why is this happening?

[bgilbert]

See discussion in #426.