Organize current tests into integration and true unit tests

[shreyb]

We have a lot of tests marked unit tests that really aren't. Make sure we mark the true unit tests "unit", and the ones that are testing one functionality, but rely on external dependencies (like fake_ifdh stuff) as "unit-dependent" or something like that, if we don't want to call them "integration". That way, we can run the true unit tests in a github action until we can figure out how to mock certain external dependencies and make them true unit tests.