$ git clone -n https://src.fedoraproject.org/rpms/ghc9.0.git /var/lib/mock/f39-build-1714128-41228/root/chroot_tmpdir/scmroot/ghc9.0
Cloning into '/var/lib/mock/f39-build-1714128-41228/root/chroot_tmpdir/scmroot/ghc9.0'...
$ git fetch origin 5a938310b0d2c95d8817dfaeac49c2e6df9587cf:KOJI_FETCH_HEAD
From https://src.fedoraproject.org/rpms/ghc9.0
 * [new ref]         5a938310b0d2c95d8817dfaeac49c2e6df9587cf -> KOJI_FETCH_HEAD
$ git reset --hard KOJI_FETCH_HEAD
HEAD is now at 5a93831 s390x is in unregisterized arches