challenge_assignments_controller currently has 59% test coverage on Coveralls:
We'd like to increase that, with an ultimate goal of 90% or greater.
How to test:
Use Coveralls to confirm that the coverage percentage has increased:
1. Go to https://coveralls.io/github/otwcode/otwarchive?branch=master
2. In the "Search" field near the "Source Files on Master" heading, enter the name of the controller: challenge_assignments_controller
3. Note the number in the "Coverage" column of the table