Ask VA 1376 - Fix postal code rules

[hemeshvpatel]

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

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

• Add postal code rules from github reference doc
• The Ask VA team owns this and it is part of our POC

Related issue(s)

• Link to ticket here: https://github.com/department-of-veterans-affairs/va.gov-team/blob/master/products/ask-va/design/Fields%2C%20options%20and%20labels/Location%20and%20postal%20code.md

Testing done

• Existing tests + manual testing of the flows

Screenshots

What areas of the site does it impact?

*This only impacts the Ask VA form

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
• [ ] Documentation has been updated (link to documentation *if necessary)
• [x] Screenshot of the developed feature is added
• [x] Accessibility testing has been performed

Error Handling

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

Authentication

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

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?