$ git clone -n https://src.fedoraproject.org/rpms/ghc-mmorph.git /var/lib/mock/f38-build-side-42-init-devel-866626-28439/root/chroot_tmpdir/scmroot/ghc-mmorph
Cloning into '/var/lib/mock/f38-build-side-42-init-devel-866626-28439/root/chroot_tmpdir/scmroot/ghc-mmorph'...
$ git fetch origin 79f2773b4bba1c3fdb0192c1e5b21ec75b473ab4:KOJI_FETCH_HEAD
From https://src.fedoraproject.org/rpms/ghc-mmorph
 * [new ref]         79f2773b4bba1c3fdb0192c1e5b21ec75b473ab4 -> KOJI_FETCH_HEAD
$ git reset --hard KOJI_FETCH_HEAD
HEAD is now at 79f2773 Convert to %autorelease and %autochangelog