Fix assessment conditions spec
Fix assessment conditions spec

- Use traits and remove assumption that user has more than 1 submission per assessment.

Coursemology/coursemology2,cysjonathan/coursemology2,cysjonathan/coursemology2,Coursemology/coursemology2,Coursemology/coursemology2,cysjonathan/coursemology2,Coursemology/coursemology2,Coursemology/coursemology2,Coursemology/coursemology2,Coursemology/coursemology2