$ git clone -n https://src.fedoraproject.org/rpms/ghc-pem.git /var/lib/mock/f40-build-2198963-51716/root/chroot_tmpdir/scmroot/ghc-pem
Cloning into '/var/lib/mock/f40-build-2198963-51716/root/chroot_tmpdir/scmroot/ghc-pem'...
$ git fetch origin 061c4de6dafaaaf298df699208c713ac7f34cf9a:KOJI_FETCH_HEAD
From https://src.fedoraproject.org/rpms/ghc-pem
 * [new ref]         061c4de6dafaaaf298df699208c713ac7f34cf9a -> KOJI_FETCH_HEAD
$ git reset --hard KOJI_FETCH_HEAD
HEAD is now at 061c4de bump release