Updated `testing/utils/conftest.py` with reliable mock data that can be used in tests; added `shared/workspaces` tests

updated coveragerc config files to reflect changes to the shared packages location and modified run-tests.sh

installs all requirements required by all 3 services; new rule: make
clean, which cleans up your Python environment and your Docker environment; make test now runs setup.py files for all packages

All enabled tests are now true unit tests with no external dependencies; new `requirements.txt` file in `test/` that installs testing requirements (`pytest`, `pytest-mock`, etc.); and `run-tests.sh` now has an extra step that installs these