$ git clone -n https://src.fedoraproject.org/rpms/kf6-kcontacts.git /var/lib/mock/f42-build-side-1-3584230-46892/root/chroot_tmpdir/scmroot/kf6-kcontacts
Cloning into '/var/lib/mock/f42-build-side-1-3584230-46892/root/chroot_tmpdir/scmroot/kf6-kcontacts'...
$ git fetch origin 65173b4dc7bb0f9a74ec3f0cfa798ab4721dc111:KOJI_FETCH_HEAD
From https://src.fedoraproject.org/rpms/kf6-kcontacts
 * [new ref]         65173b4dc7bb0f9a74ec3f0cfa798ab4721dc111 -> KOJI_FETCH_HEAD
$ git reset --hard KOJI_FETCH_HEAD
HEAD is now at 65173b4 6.16.0