$ git clone -n https://src.fedoraproject.org/rpms/ocaml-base.git /var/lib/mock/f38-build-side-42-init-devel-628173-26370/root/chroot_tmpdir/scmroot/ocaml-base
Cloning into '/var/lib/mock/f38-build-side-42-init-devel-628173-26370/root/chroot_tmpdir/scmroot/ocaml-base'...
$ git fetch origin dcbe41532f6bbdcb7d607cdf98d72fbac3d80de9:KOJI_FETCH_HEAD
From https://src.fedoraproject.org/rpms/ocaml-base
 * [new ref]         dcbe41532f6bbdcb7d607cdf98d72fbac3d80de9 -> KOJI_FETCH_HEAD
$ git reset --hard KOJI_FETCH_HEAD
HEAD is now at dcbe415 Rebuild OCaml packages for F38