.arcconfig

rev-branch-cache: add a function to generate a part

The function is able to produce a rbc part consumed by the function introduced
into previous changesets. More details on usage and impact in the next
changesets.

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