[BUG] Decouple tests from source code structure/response values

[dbbaughe]

Describe the bug
Our tests missed this breaking change: #108
This is because the test imports the source code setting value and uses it in the test. So when the source code and test was changed it wasn't clear that the actual response of the API had changed as the tests continued passing with the new setting key value.

For these things that should not change, we should hardcode the value in the tests themselves to ensure that if someone accidentally changes the source code it is caught in the test.

[dblock]

Maybe we can get something methodical that records API requests and compares outputs?

[bowenlan-amzn]

Maybe this can be part of backward compatibility tests #125