Execute Harbormaster buildable filtering properly from HarbormasterBuildSearchEngine
Ref T11473. When running harbormaster.build.search with a buildables constraint, the constraint doesn't get passed to the Query and so currently has no effect.
This piece of logic was just accidentally omitted from D16356. It is probably not used anywhere today and doesn't show up in the UI, so it's easy to overlook (I missed it in review, too).
Test Plan: Ran harbormaster.build.search with a buildables constraint, got expected filtering.
Reviewers: yelirekim, chad
Reviewed By: chad
Maniphest Tasks: T11473
Differential Revision: https://secure.phabricator.com/D16395