Remove unused VAOS V1 APIs

Are you removing, renaming or moving a folder in this PR?

[x] No, I'm not changing any folders (skip to TeamSites and delete the rest of this section)
[ ] Yes, I'm removing, renaming or moving a folder

:warning: TeamSites :warning:

Examples of a TeamSite: https://va.gov/health and https://benefits.va.gov/benefits/. This scenario is also referred to as the "injected" header and footer. You can reach out in the #sitewide-public-websites Slack channel for questions.

Did you change site-wide styles, platform utilities or other infrastructure?

[x] No
[ ] Yes, and I used the proxy-rewrite steps to test the injected header scenario

Summary

This PR removes two V1 API util functions that are no longer used
Appointments (VAOS) Team
This is not behind a Flipper

Related issue(s)

https://github.com/department-of-veterans-affairs/va.gov-team/issues/95620

Testing done

Removed 1 redundant unit test and ensured all existing unit and e2e tests pass

Screenshots

N/A

What areas of the site does it impact?

Appointments (VAOS)

Acceptance criteria

Quality Assurance & Testing

[x] I fixed|updated|added unit tests and integration tests for each feature (if applicable).
[x] No sensitive information (i.e. PII/credentials/internal URLs/etc.) is captured in logging, hardcoded, or specs
[x] Linting warnings have been addressed
[x] Documentation has been updated (link to documentation *if necessary)
[ ] Screenshot of the developed feature is added
[x] Accessibility testing has been performed

Error Handling

[x] Browser console contains no warnings or errors.
[x] Events are being sent to the appropriate logging solution
[x] Feature/bug has a monitor built into Datadog or Grafana (if applicable)

Authentication

[ ] Did you login to a local build and verify all authenticated routes work as expected with a test user

department-of-veterans-affairs / vets-website

Remove unused VAOS V1 APIs #33160