Ability to perform schema validation for config CRUD APIs #1660

Challenge

• No way to do a schema check for configs being written when using non K8s config adapters.

Solution

1. Add a json schema / openapi validation step for the apply config endpoint.
2. We can use the JSON schema reflection library to figure out the schema of a source when it registers itself with the Source Manager.
3. Source Manager can store the json schema generated in a global map against the gvr
4. Handler for config apply endpoint can fetch this jsonschema from the Source Manager App before passing the data to the ConfigManager