$ git clone -n https://src.fedoraproject.org/rpms/ghc-reducers.git /var/lib/mock/f45-build-10676-419/root/chroot_tmpdir/scmroot/ghc-reducers
Cloning into '/var/lib/mock/f45-build-10676-419/root/chroot_tmpdir/scmroot/ghc-reducers'...
$ git fetch origin 64c17d53761151653ac6c8a9dc2b1aa7f8c3b70e:KOJI_FETCH_HEAD
From https://src.fedoraproject.org/rpms/ghc-reducers
 * [new ref]         64c17d53761151653ac6c8a9dc2b1aa7f8c3b70e -> KOJI_FETCH_HEAD
$ git reset --hard KOJI_FETCH_HEAD
HEAD is now at 64c17d5 Rebuilt for https://fedoraproject.org/wiki/Fedora_45_Mass_Rebuild