$ git clone -n https://src.fedoraproject.org/rpms/planets.git /var/lib/mock/f39-build-1501833-34870/root/chroot_tmpdir/scmroot/planets
Cloning into '/var/lib/mock/f39-build-1501833-34870/root/chroot_tmpdir/scmroot/planets'...
$ git fetch origin ee62813b540355c6d1368b71810106b908399e31:KOJI_FETCH_HEAD
From https://src.fedoraproject.org/rpms/planets
 * [new ref]         ee62813b540355c6d1368b71810106b908399e31 -> KOJI_FETCH_HEAD
$ git reset --hard KOJI_FETCH_HEAD
HEAD is now at ee62813 Minor spec file cleanups