Improve speed of tests

[auscompgeek]

Currently, the tests (specifically the game tests) take a tad longer than I would hope. The tests are great, but they could be a bit faster.

[lkw657]

The testing code is currently running a game for every difficulty in every category with different final scores. This is completely unnecessary since it is just testing the same code execution path an excessive amount of times. It would be better if the tests had their own smaller version of the dummy data with different test cases such as less than 5 questions or an empty difficulty. In addition to it being smaller and more selective it would also mean that the same test cases are being run even if the state of the dummy data changes (i.e. more questions are added).