$ git clone -n https://src.fedoraproject.org/rpms/ghc-data-fix.git /var/lib/mock/f39-build-2196953-51619/root/chroot_tmpdir/scmroot/ghc-data-fix
Cloning into '/var/lib/mock/f39-build-2196953-51619/root/chroot_tmpdir/scmroot/ghc-data-fix'...
$ git fetch origin 9978dd13b9cdc22df00db9ff4d50f5abf7b0a197:KOJI_FETCH_HEAD
From https://src.fedoraproject.org/rpms/ghc-data-fix
 * [new ref]         9978dd13b9cdc22df00db9ff4d50f5abf7b0a197 -> KOJI_FETCH_HEAD
$ git reset --hard KOJI_FETCH_HEAD
HEAD is now at 9978dd1 revised .cabal file