$ git clone -n https://src.fedoraproject.org/rpms/kgamma.git /var/lib/mock/f40-build-2475592-61566/root/chroot_tmpdir/scmroot/kgamma
Cloning into '/var/lib/mock/f40-build-2475592-61566/root/chroot_tmpdir/scmroot/kgamma'...
$ git fetch origin bcf92bab0c23597b23858e34cea31cb5d20b74d1:KOJI_FETCH_HEAD
From https://src.fedoraproject.org/rpms/kgamma
 * [new ref]         bcf92bab0c23597b23858e34cea31cb5d20b74d1 -> KOJI_FETCH_HEAD
$ git reset --hard KOJI_FETCH_HEAD
HEAD is now at bcf92ba 6.0.0