[Testing] Add scaffolding for MMIS tests

[thetif]

Description and related issues

We are going to need more tests for MMIS APDs soon. Create a suite for MMIS tests. Add another parallelization to the CI. Go through the existing HITECH tests and see if we need to clean anything up to make it easier to write MMIS tests. This doesn't include copying over the tests and changing them for MMIS.

This task is done when…

• [ ] MMIS test file is in place
• [ ] the file runs in a separate parallel run on CircleCI