[dbx-75526.2] add default state to form526 submissions

[SamStuckey]

Summary

This is PR 2 of 3 to add state to our Form526Submission model. It follows the first PR here, per the documentation about migrations and default values here

• *This work is behind a feature toggle (flipper): NO
• add a default value of 'unprocessed' to our form526_submissions table in the aasm_state column

NOTE: this is not a wholeistic solution for end-to-end tracking. This work simply allows us a persistent, simple, queryable, and non-human-error-prone way to track submission state outside of the normal submission flow, ie remediation. There is a pretty good chance that this will be replaced in the next year or so with a global UUID for submissions (at least that's the current thinking).

Related issue(s)

• Ticket
• First PR
• Initial PR (deprecated) where the 3 PR structure was requested
• Feature / Implementation Documentation

Testing done

• New code is covered by unit tests - No. tests will be added in the next PR when model logic is added. there is nothing to test.
• Model instantiated and manipulated, nothing else to test

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 or Grafana (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

[ryan-mcneil]

👍