evolve: mark new hash-salting extras keys as uninteresting for effect flag The user doesn't care if the `evolve_source_local`/`evolve_source_other` values in the extras changed, so this patch adds them to the blacklist that already exists for that purpose. This should also fix the flakiness we've seen in some tests. The flakiness seemed to stem from `mercurial.obsutil.geteffectflag()` not sorting extras keys. That means we ran into it relatively often for the `evolve_source_local`/`evolve_source_other` keys because there were two of them. That sorting bug should be fixed upstream.

#require test-repo

  $ checkcm() {
  >   if ! (which check-manifest > /dev/null); then
  >     echo skipped: missing tool: check-manifest;
  >     exit 80;
  >   fi;
  > };
  $ checkcm
  $ cat << EOF >> $HGRCPATH
  > [experimental]
  > evolution=all
  > EOF

Run check manifest:

  $ cd $TESTDIR/..
  $ check-manifest
  lists of files in version control and sdist match