Reject missing icn on HLR\SC index

[michelpmcdonald]

Summary

The index endpoint for both Higher Level Reviews and Supplemental Claims were both leaking data when called without an ICN. They were both returning appeals that did not have an ICN because we unintendedly issuing a query like ~"where ICN = nil" when index was called without an ICN provided.

Added code to reject appeals index calls without an X-VA-ICN header provided.

My banana -peels team owns this code

Related issue(s)

API-23079

Testing done

Prior to this change, calls to index without supplying and ICN were not rejected AND those calls were returning ALL appeals records that did not have an ICN in the veterans-icn column

Added unit test to make sure index calls without an X-VA-ICN header are rejected

Screenshots

Note: Optional

What areas of the site does it impact?

index route for Higher Level Reviews and Supplemental Claims

Acceptance criteria

• I fixed|updated|added unit tests and integration tests for each feature (if applicable).
• No error nor warning in the console.
• Events are being sent to the appropriate logging solution

[kristen-brown]

LGTM!