$ git clone -n https://src.fedoraproject.org/rpms/gap-pkg-cryst.git /var/lib/mock/f40-build-2687284-68090/root/chroot_tmpdir/scmroot/gap-pkg-cryst
Cloning into '/var/lib/mock/f40-build-2687284-68090/root/chroot_tmpdir/scmroot/gap-pkg-cryst'...
$ git fetch origin e6ecde85085fde40f4f20b5a516689df39c54bbc:KOJI_FETCH_HEAD
From https://src.fedoraproject.org/rpms/gap-pkg-cryst
 * [new ref]         e6ecde85085fde40f4f20b5a516689df39c54bbc -> KOJI_FETCH_HEAD
$ git reset --hard KOJI_FETCH_HEAD
HEAD is now at e6ecde8 Rebuild for gap 4.13.0