$ git clone -n https://src.fedoraproject.org/rpms/ocaml-ppx-stable-witness.git /var/lib/mock/f42-build-3384176-45084/root/chroot_tmpdir/scmroot/ocaml-ppx-stable-witness
Cloning into '/var/lib/mock/f42-build-3384176-45084/root/chroot_tmpdir/scmroot/ocaml-ppx-stable-witness'...
$ git fetch origin 0b11c5f4b69de411247f0ab82d0e78e139fe2a9c:KOJI_FETCH_HEAD
From https://src.fedoraproject.org/rpms/ocaml-ppx-stable-witness
 * [new ref]         0b11c5f4b69de411247f0ab82d0e78e139fe2a9c -> KOJI_FETCH_HEAD
$ git reset --hard KOJI_FETCH_HEAD
HEAD is now at 0b11c5f Rebuild for ocaml-ppxlib 0.35.0