$ git clone -n https://src.fedoraproject.org/rpms/happy.git /var/lib/mock/f45-build-13323-449/root/chroot_tmpdir/scmroot/happy
Cloning into '/var/lib/mock/f45-build-13323-449/root/chroot_tmpdir/scmroot/happy'...
$ git fetch origin 9942ccc64550185aeb1c29838fe723cde947e5a5:KOJI_FETCH_HEAD
From https://src.fedoraproject.org/rpms/happy
 * [new ref]         9942ccc64550185aeb1c29838fe723cde947e5a5 -> KOJI_FETCH_HEAD
$ git reset --hard KOJI_FETCH_HEAD
HEAD is now at 9942ccc Rebuilt for https://fedoraproject.org/wiki/Fedora_45_Mass_Rebuild