$ git clone -n https://src.fedoraproject.org/rpms/erlang-ranch.git /var/lib/mock/f41-build-1057788-19407/root/chroot_tmpdir/scmroot/erlang-ranch
Cloning into '/var/lib/mock/f41-build-1057788-19407/root/chroot_tmpdir/scmroot/erlang-ranch'...
$ git fetch origin 981b6cbed5643372ce3a409c553bab2b4e81f5d9:KOJI_FETCH_HEAD
From https://src.fedoraproject.org/rpms/erlang-ranch
 * [new ref]         981b6cbed5643372ce3a409c553bab2b4e81f5d9 -> KOJI_FETCH_HEAD
$ git reset --hard KOJI_FETCH_HEAD
HEAD is now at 981b6cb Removed unnecessary line