.arcconfig

tests: fix style issue of importing order in test-lock.py

test-lock.py is excluded in test-check-module-imports.t, because
import-checker.py reports that some stdlibs are imported after local
silenttestrunner module.

I can not found out any reason why tests/silenttestrunner.py should be
imported before some stdlibs from the point of functionality view.

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