$ git clone -n https://src.fedoraproject.org/rpms/ghc-gi-gmodule.git /var/lib/mock/f38-build-side-42-init-devel-1086710-30037/root/chroot_tmpdir/scmroot/ghc-gi-gmodule
Cloning into '/var/lib/mock/f38-build-side-42-init-devel-1086710-30037/root/chroot_tmpdir/scmroot/ghc-gi-gmodule'...
$ git fetch origin cdf584cd33fd7148898f979360c713fa060136d9:KOJI_FETCH_HEAD
From https://src.fedoraproject.org/rpms/ghc-gi-gmodule
 * [new ref]         cdf584cd33fd7148898f979360c713fa060136d9 -> KOJI_FETCH_HEAD
$ git reset --hard KOJI_FETCH_HEAD
HEAD is now at cdf584c rebuild