$ git clone -n https://src.fedoraproject.org/rpms/ghc-chunked-data.git /var/lib/mock/f41-build-839108-159992/root/chroot_tmpdir/scmroot/ghc-chunked-data
Cloning into '/var/lib/mock/f41-build-839108-159992/root/chroot_tmpdir/scmroot/ghc-chunked-data'...
$ git fetch origin b20b4c95fc37857f54c916dd790bd3545aa6923c:KOJI_FETCH_HEAD
From https://src.fedoraproject.org/rpms/ghc-chunked-data
 * [new ref]         b20b4c95fc37857f54c916dd790bd3545aa6923c -> KOJI_FETCH_HEAD
$ git reset --hard KOJI_FETCH_HEAD
HEAD is now at b20b4c9 bump release