$ git clone -n https://src.fedoraproject.org/rpms/shunit2.git /var/lib/mock/f45-build-35931-700/root/chroot_tmpdir/scmroot/shunit2
Cloning into '/var/lib/mock/f45-build-35931-700/root/chroot_tmpdir/scmroot/shunit2'...
$ git fetch origin 9ada0fb5ddd03a39476d78fbdc0970d427ab2428:KOJI_FETCH_HEAD
From https://src.fedoraproject.org/rpms/shunit2
 * [new ref]         9ada0fb5ddd03a39476d78fbdc0970d427ab2428 -> KOJI_FETCH_HEAD
$ git reset --hard KOJI_FETCH_HEAD
HEAD is now at 9ada0fb Rebuilt for https://fedoraproject.org/wiki/Fedora_45_Mass_Rebuild