$ git clone -n https://src.fedoraproject.org/rpms/unlambda.git /var/lib/mock/f38-build-side-42-init-devel-696738-27006/root/chroot_tmpdir/scmroot/unlambda
Cloning into '/var/lib/mock/f38-build-side-42-init-devel-696738-27006/root/chroot_tmpdir/scmroot/unlambda'...
$ git fetch origin ab49f96ac32f11ea957edba874e6a70a1e6593a6:KOJI_FETCH_HEAD
From https://src.fedoraproject.org/rpms/unlambda
 * [new ref]         ab49f96ac32f11ea957edba874e6a70a1e6593a6 -> KOJI_FETCH_HEAD
$ git reset --hard KOJI_FETCH_HEAD
HEAD is now at ab49f96 bump release