Description of changes

In data_validation/__main__.py we used to add the raw connection info into the JSON. The PR removes that code and adds a test to ensure that the resulting JSON executes correctly (i.e. the fields were not required).

Issues to be closed

Closes #1738

Checklist

• I have followed the CONTRIBUTING Guide.
• I have commented my code, particularly in hard-to-understand areas
• I have updated any relevant documentation to reflect my changes, if applicable
• I have added unit and/or integration tests relevant to my change as needed
• I have already checked locally that all unit tests and linting are passing (use the tests/local_check.sh script)
• I have manually executed end-to-end testing (E2E) with the affected databases/engines