.arcconfig

copies: delete misplaced comment

The comment was added in 78d760aa3607 (duplicatecopies: do not mark
items not in the dirstate as copies, 2013-03-28). It became misplaced
in 3666331164bb (cmdutil: add copy-filtering support to
duplicatecopies, 2014-06-07). Then the relevant code was moved far
away in 754b5117622f (context: add workingfilectx.markcopied,
2017-10-15).

Differential Revision: https://phab.mercurial-scm.org/D6352

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