.arcconfig

rawdata: add the method to bundlerevlog

The bundlerepo logic has its own `revision` method on its own `revlog` object.
We need to "implement" `rawdata` there too.

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