move test components into a aggregator module since we should not publish them

[cameronlee314]

Currently, artifacts are published for the test modules which are just needed for integration tests. In the future, we may add more test modules for other integration testing, so it would be good to avoid having a separate module/artifact for each of those. This change reorganizes the project structure so all of the test modules are under a single aggregator module. This is nice because the test modules are now all under a single module and it makes it easy to skip the deploy step for all of these modules when releasing.