$ git clone -n https://src.fedoraproject.org/rpms/kf6-prison.git /var/lib/mock/f42-build-863225-171512/root/chroot_tmpdir/scmroot/kf6-prison
Cloning into '/var/lib/mock/f42-build-863225-171512/root/chroot_tmpdir/scmroot/kf6-prison'...
$ git fetch origin f9163a4d598fd1d68279e4fb13c2e0bc8a7cce23:KOJI_FETCH_HEAD
From https://src.fedoraproject.org/rpms/kf6-prison
 * [new ref]         f9163a4d598fd1d68279e4fb13c2e0bc8a7cce23 -> KOJI_FETCH_HEAD
$ git reset --hard KOJI_FETCH_HEAD
HEAD is now at f9163a4 Frameworks 6.9