MHV Secondary Nav (A11y) - Announce current selection

[nichia]

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

• 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

⚠️ TeamSites ⚠️

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?

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

Summary

Add 'aria-current="page"' to the selected Nav bar to enable screen reader to correctly announce the current page location.

Related issue(s)

department-of-veterans-affairs/va.gov-team#93727

Testing done

• Visually check that aria-current="page" is an attribute of the active/selected 'a' tag.
• Test with VoiceOver and Chrome browser (my Safari browser is not yet setup locally to run the app) to verify voiceOver is announcing the current page

Screenshots

No visual UI change.

What areas of the site does it impact?

MHV Secondary Navigation

Acceptance criteria

• When a user focuses on the secondary nav item/section that is visually highlighted to indicate the page's location, screen reader indicates this as well
• QA review
• A11y review

Quality Assurance & Testing

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

Error Handling

• 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

• 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?