$ git clone -n https://src.fedoraproject.org/rpms/ocaml-obuild.git /var/lib/mock/f40-build-2238717-53584/root/chroot_tmpdir/scmroot/ocaml-obuild
Cloning into '/var/lib/mock/f40-build-2238717-53584/root/chroot_tmpdir/scmroot/ocaml-obuild'...
$ git fetch origin 917cffbf4f62a6e191dd9a71c8d3431843701568:KOJI_FETCH_HEAD
From https://src.fedoraproject.org/rpms/ocaml-obuild
 * [new ref]         917cffbf4f62a6e191dd9a71c8d3431843701568 -> KOJI_FETCH_HEAD
$ git reset --hard KOJI_FETCH_HEAD
HEAD is now at 917cffb Bump release and rebuild