$ git clone -n https://src.fedoraproject.org/rpms/ksystemstats.git /var/lib/mock/f42-build-side-1-3577610-46813/root/chroot_tmpdir/scmroot/ksystemstats
Cloning into '/var/lib/mock/f42-build-side-1-3577610-46813/root/chroot_tmpdir/scmroot/ksystemstats'...
$ git fetch origin 487318c98f44faf823d6672ff7702d44f043980c:KOJI_FETCH_HEAD
From https://src.fedoraproject.org/rpms/ksystemstats
 * [new ref]         487318c98f44faf823d6672ff7702d44f043980c -> KOJI_FETCH_HEAD
$ git reset --hard KOJI_FETCH_HEAD
HEAD is now at 487318c 6.4.1