$ git clone -n https://src.fedoraproject.org/rpms/kmail.git /var/lib/mock/f39-build-1966743-43294/root/chroot_tmpdir/scmroot/kmail
Cloning into '/var/lib/mock/f39-build-1966743-43294/root/chroot_tmpdir/scmroot/kmail'...
$ git fetch origin b558467168194ba32931b7412f4811cbb22a6ff6:KOJI_FETCH_HEAD
From https://src.fedoraproject.org/rpms/kmail
 * [new ref]         b558467168194ba32931b7412f4811cbb22a6ff6 -> KOJI_FETCH_HEAD
$ git reset --hard KOJI_FETCH_HEAD
HEAD is now at b558467 23.08.3