feat: Add schema validation tests

[Leo10Gama]

Why is this change necessary?

To ensure the generated schema is correct, we need to test it against various config files. This will ensure that tests that should validate against the schema will validate, while tests that shouldn't validate against the schema won't.

How does it address the issue?

A new test file, test_schema_validation.py has been created to validate various config files against the generated schema. In addition, a testdata folder has been added, with various hand-written config files to test each command, as well as prevent invalid schemas.

What side effects does this change have?

New tests have been added, to test that config files will and won't validate against the schema.

Mandatory Checklist

PRs will only be reviewed after checklist is complete

• Add input/output type hints to new functions/methods
• Write design document if needed (Do I need to write a design document?)
• Write/update unit tests
• Write/update integration tests
• Write/update functional tests if needed
• make pr passes
• make update-reproducible-reqs if dependencies were changed
• Write documentation

By submitting this pull request, I confirm that my contribution is made under the terms of the Apache 2.0 license.