$ git clone -n https://src.fedoraproject.org/rpms/ocaml-fieldslib.git /var/lib/mock/f38-build-side-42-init-devel-678040-26695/root/chroot_tmpdir/scmroot/ocaml-fieldslib
Cloning into '/var/lib/mock/f38-build-side-42-init-devel-678040-26695/root/chroot_tmpdir/scmroot/ocaml-fieldslib'...
$ git fetch origin 684979dc775228810c04d0a42aace901bd15edd2:KOJI_FETCH_HEAD
From https://src.fedoraproject.org/rpms/ocaml-fieldslib
 * [new ref]         684979dc775228810c04d0a42aace901bd15edd2 -> KOJI_FETCH_HEAD
$ git reset --hard KOJI_FETCH_HEAD
HEAD is now at 684979d Rebuild OCaml packages for F38