$ git clone -n https://src.fedoraproject.org/rpms/lua-mpack.git /var/lib/mock/f45-build-17682-502/root/chroot_tmpdir/scmroot/lua-mpack
Cloning into '/var/lib/mock/f45-build-17682-502/root/chroot_tmpdir/scmroot/lua-mpack'...
$ git fetch origin d47af86fb0f7f33d58c9c55faf106da27701c94e:KOJI_FETCH_HEAD
From https://src.fedoraproject.org/rpms/lua-mpack
 * [new ref]         d47af86fb0f7f33d58c9c55faf106da27701c94e -> KOJI_FETCH_HEAD
$ git reset --hard KOJI_FETCH_HEAD
HEAD is now at d47af86 Rebuilt for https://fedoraproject.org/wiki/Fedora_45_Mass_Rebuild