$ git clone -n https://src.fedoraproject.org/rpms/xu4.git /var/lib/mock/f41-build-2044770-25295/root/chroot_tmpdir/scmroot/xu4
Cloning into '/var/lib/mock/f41-build-2044770-25295/root/chroot_tmpdir/scmroot/xu4'...
$ git fetch origin 4a749afbeeabb9b47bec8d70f8dd687b6c22dc1a:KOJI_FETCH_HEAD
From https://src.fedoraproject.org/rpms/xu4
 * [new ref]         4a749afbeeabb9b47bec8d70f8dd687b6c22dc1a -> KOJI_FETCH_HEAD
$ git reset --hard KOJI_FETCH_HEAD
HEAD is now at 4a749af Orphaned for 6+ weeks