$ git clone -n https://src.fedoraproject.org/rpms/kf6-kdesu.git /var/lib/mock/f42-build-862034-170551/root/chroot_tmpdir/scmroot/kf6-kdesu
Cloning into '/var/lib/mock/f42-build-862034-170551/root/chroot_tmpdir/scmroot/kf6-kdesu'...
$ git fetch origin 6b0e967ba880b5e209b35c31707541130df65627:KOJI_FETCH_HEAD
From https://src.fedoraproject.org/rpms/kf6-kdesu
 * [new ref]         6b0e967ba880b5e209b35c31707541130df65627 -> KOJI_FETCH_HEAD
$ git reset --hard KOJI_FETCH_HEAD
HEAD is now at 6b0e967 6.8.0