.arcconfig

extensions: drop dead code trying to exclude deprecated disabled commands

Here 'ext' is a tuple, which means ext.__doc__ describes about the Python
tuple type. Fixing this would break 'hg help glog', which currently shows
some nice explanation, so this patch just removes the dead code.

  $ hg help glog
  'glog' is provided by the following extension:

      graphlog      command to view revision graphs from a shell (DEPRECATED)

  (use 'hg help extensions' for information on enabling extensions)

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