tests/test-check-config.t

run-tests: handle json.dumps divergence

In py2, json.dumps includes a trailing space after a comma at the
end of lines. The py3 behavior which omits the trailing space is
preferable, so we're going to strip it.

#require test-repo

  $ cd "$TESTDIR"/..

New errors are not allowed. Warnings are strongly discouraged.

  $ hg files "set:(**.py or **.txt) - tests/**" | sed 's|\\|/|g' |
  >   python contrib/check-config.py