So you might want to ping @Lyla-Fischer and @talbs on this, but can't we do a check on `self.completed_at` and just return the scores from assessments at this point, instead of recalculating them? I would really like to keep it so that `completed_at` and `scored` attributes are only written once when the user has crossed over what the finish line was at that point. It's less confusing for the user and slightly easier for us to do caching (We'd cache based on PeerWorkflow.id + completed_at and store the whole return dict so we never need to query Assessments.)