D5120: match: fix up a repr to not crash on Python 3

[durin42 (Augie Fackler)]

durin42 added inline comments.

INLINE COMMENTS

> martinvonz wrote in match.py:1176
> sorted() seems to return a list on py3, so maybe the list() call is unnecessary?

I could swear I've seen cases where it's not, but maybe we can prune this out after the freeze?

REPOSITORY
  rHG Mercurial

REVISION DETAIL
  https://phab.mercurial-scm.org/D5120

To: durin42, #hg-reviewers, pulkit
Cc: martinvonz, mercurial-devel