view .arcconfig @ 48283:ebac18733142

typing: add a few assertions to revlog.py to help pytype

I've seen this before, but this was seen as potentially `None` with pytype
2021.10.18.

Differential Revision: https://phab.mercurial-scm.org/D11718

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