$ git clone -n https://src.fedoraproject.org/rpms/rpkg.git /var/lib/mock/f45-build-34747-691/root/chroot_tmpdir/scmroot/rpkg
Cloning into '/var/lib/mock/f45-build-34747-691/root/chroot_tmpdir/scmroot/rpkg'...
$ git fetch origin ccb7313fa6a1b1eec306746e7f97697c673acf66:KOJI_FETCH_HEAD
From https://src.fedoraproject.org/rpms/rpkg
 * [new ref]         ccb7313fa6a1b1eec306746e7f97697c673acf66 -> KOJI_FETCH_HEAD
$ git reset --hard KOJI_FETCH_HEAD
HEAD is now at ccb7313 New release 1.70