$ git clone -n https://src.fedoraproject.org/rpms/ocaml-compiler-libs-janestreet.git /var/lib/mock/f38-build-side-42-init-devel-715356-27290/root/chroot_tmpdir/scmroot/ocaml-compiler-libs-janestreet
Cloning into '/var/lib/mock/f38-build-side-42-init-devel-715356-27290/root/chroot_tmpdir/scmroot/ocaml-compiler-libs-janestreet'...
$ git fetch origin 87b6608e6da10052a8cba54376163e1afd1b0d9d:KOJI_FETCH_HEAD
From https://src.fedoraproject.org/rpms/ocaml-compiler-libs-janestreet
 * [new ref]         87b6608e6da10052a8cba54376163e1afd1b0d9d -> KOJI_FETCH_HEAD
$ git reset --hard KOJI_FETCH_HEAD
HEAD is now at 87b6608 Rebuild OCaml packages for F38