#90130 [10-10EZR]: Adds ezr_tera_branching_enabled feature toggle

[JoshingYou1]

Summary

• This work is behind a feature toggle (flipper): NO

Related issue(s)

• https://app.zenhub.com/workspaces/10-10-health-apps-5fff0cfd1462b6000e320fc7/issues/gh/department-of-veterans-affairs/va.gov-team/90130

Screenshots

Note: Optional

What areas of the site does it impact?

10-10EZR form

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?

[github-actions]

Backend-review-group approval confirmed.