$ git clone -n https://src.fedoraproject.org/rpms/kf6-prison.git /var/lib/mock/f41-build-side-1-2647385-27301/root/chroot_tmpdir/scmroot/kf6-prison
Cloning into '/var/lib/mock/f41-build-side-1-2647385-27301/root/chroot_tmpdir/scmroot/kf6-prison'...
$ git fetch origin b1346fb31d5c05c4a5e1b41f6f7f6a4d5d746e06:KOJI_FETCH_HEAD
From https://src.fedoraproject.org/rpms/kf6-prison
 * [new ref]         b1346fb31d5c05c4a5e1b41f6f7f6a4d5d746e06 -> KOJI_FETCH_HEAD
$ git reset --hard KOJI_FETCH_HEAD
HEAD is now at b1346fb 6.5.0