$ git clone -n https://src.fedoraproject.org/rpms/ocaml-ppx-base.git /var/lib/mock/f42-build-865812-173520/root/chroot_tmpdir/scmroot/ocaml-ppx-base
Cloning into '/var/lib/mock/f42-build-865812-173520/root/chroot_tmpdir/scmroot/ocaml-ppx-base'...
$ git fetch origin bc66b59fe6d0e745ea62a83875239e3cb2332a5b:KOJI_FETCH_HEAD
From https://src.fedoraproject.org/rpms/ocaml-ppx-base
 * [new ref]         bc66b59fe6d0e745ea62a83875239e3cb2332a5b -> KOJI_FETCH_HEAD
$ git reset --hard KOJI_FETCH_HEAD
HEAD is now at bc66b59 OCaml 5.3.0 rebuild for Fedora 42