DDG::Spice::Movie: refine movie trigger.
Narrows spice triggers to 'rotten tomatoes' and 'rotten' since we'll now be depending on deep triggers for most queries (e.g. 'the graduate movie'). Also updated the tests.

https://app.asana.com/0/inbox/8969260899168/15182251387711/16016849000155
Merge pull request #1067 from duckduckgo/nilnilnil/refine-movie-info-trigger

DDG::Spice::Movie: refine movie trigger.