.arcconfig

path: use `get_unique_pull_path_obj` in `hg relink`

This is not really needed, but that help removing caller of the older function.

{
    "conduit_uri": "https://phab.mercurial-scm.org/api",
    "phabricator.uri": "https://phab.mercurial-scm.org/",
    "repository.callsign": "HG",
    "arc.land.onto.default": "@",
    "base": "hg:.^"
}