$ git clone -n https://src.fedoraproject.org/rpms/ghc-NumInstances.git /var/lib/mock/f45-build-9924-411/root/chroot_tmpdir/scmroot/ghc-NumInstances
Cloning into '/var/lib/mock/f45-build-9924-411/root/chroot_tmpdir/scmroot/ghc-NumInstances'...
$ git fetch origin 9ba5a02016ed439b6005eaf4bfd3a267fbfed53c:KOJI_FETCH_HEAD
From https://src.fedoraproject.org/rpms/ghc-NumInstances
 * [new ref]         9ba5a02016ed439b6005eaf4bfd3a267fbfed53c -> KOJI_FETCH_HEAD
$ git reset --hard KOJI_FETCH_HEAD
HEAD is now at 9ba5a02 Rebuilt for https://fedoraproject.org/wiki/Fedora_45_Mass_Rebuild