Publish rules YAML schema for validation

[jpower432]

Is your feature request related to a problem? Please describe.

Allow the rules YAML to be validated during authoring through IDEs or for pre-submission schema validation. Rules with invalid schemas cannot be checked pre-commit currently.

Describe the solution you'd like

The TrestleRule model is defined with pydantic. Used pydantic features to generate a JSON schema.

Describe alternatives you've considered
None

Additional context
N/A