$ git clone -n https://src.fedoraproject.org/rpms/erlang-ranch.git /var/lib/mock/f40-build-1777692-24803/root/chroot_tmpdir/scmroot/erlang-ranch
Cloning into '/var/lib/mock/f40-build-1777692-24803/root/chroot_tmpdir/scmroot/erlang-ranch'...
$ git fetch origin 561d35244998f071f2ffd5a9cefeaba18f1e64d4:KOJI_FETCH_HEAD
From https://src.fedoraproject.org/rpms/erlang-ranch
 * [new ref]         561d35244998f071f2ffd5a9cefeaba18f1e64d4 -> KOJI_FETCH_HEAD
$ git reset --hard KOJI_FETCH_HEAD
HEAD is now at 561d352 Unbundle ct_helper