Mobile debts model

[Tonksthebear]

Note: Delete the description statements, complete each step. None are optional, but can be justified as to why they cannot be completed as written. Provide known gaps to testing that may raise the risk of merging to production.

Summary

This adds a model to the debt endpoint in order to ensure we get alerted when there are schema changes

Related issue(s)

department-of-veterans-affairs/va-mobile-app#8148

Testing done

Existing tests cover the changes

Screenshots

Note: Optional

What areas of the site does it impact?

(Describe what parts of the site are impacted andifcode touched other areas)

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
• Documentation has been updated (link to documentation)
• No sensitive information (i.e. PII/credentials/internal URLs/etc.) is captured in logging, hardcoded, or specs
• Feature/bug has a monitor built into Datadog (if applicable)
• If app impacted requires authentication, did you login to a local build and verify all authenticated routes work as expected
• I added a screenshot of the developed feature

Requested Feedback

(OPTIONAL)What should the reviewers know in addition to the above. Is there anything specific you wish the reviewer to assist with. Do you have any concerns with this PR, why?

[aherzberg]

There's enough going on here and the debt specs are minimal enough that i think it'd be worth adding an explicit check of the response before and after these changes in the spec to make sure nothing has changed. Unless you'd done that manually already in your own env