$ git clone -n https://src.fedoraproject.org/rpms/mkrdns.git /var/lib/mock/f45-build-18951-538/root/chroot_tmpdir/scmroot/mkrdns
Cloning into '/var/lib/mock/f45-build-18951-538/root/chroot_tmpdir/scmroot/mkrdns'...
$ git fetch origin 1320af1bd63ba990a4e90f988ab78c1ead0f93f7:KOJI_FETCH_HEAD
From https://src.fedoraproject.org/rpms/mkrdns
 * [new ref]         1320af1bd63ba990a4e90f988ab78c1ead0f93f7 -> KOJI_FETCH_HEAD
$ git reset --hard KOJI_FETCH_HEAD
HEAD is now at 1320af1 Rebuilt for https://fedoraproject.org/wiki/Fedora_45_Mass_Rebuild