Add Custom Field Examples

[amanifarooque]

Using existing metadata and populating it into custom fields for faceted search testing.

This is in support of testing https://github.com/GSA/search-gov/pull/950

PR Checklist

• [x] Test Federalist Preview link for your branch for functionality - make sure all links and buttons work, javascript works as intended, and updates display as expected
• [N/A] Conduct a HemingwayApp review of the content for plain language. Request plain language review in #helpwanted if needed before merging this PR
• [N/A] Conduct a Lighthouse Audit via Chrome Developer Tools. Identify any issues that must be addressed before merging, and fix
• [x] Ensure no non-public information is published in the commit messages

[amanifarooque]

Custom 1 and Custom 3 populated: https://cg-a72b65a7-73f0-4859-a1d7-dc953cf6ade8.app.cloud.gov/preview/gsa/search-gov-website/afarooque/metadata/status.html

Custom 2 and Custom 3 populated: https://cg-a72b65a7-73f0-4859-a1d7-dc953cf6ade8.app.cloud.gov/preview/gsa/search-gov-website/afarooque/metadata/about/updates/releases/april-2022.html

[amanifarooque]

Good thought for sure, I think we do want an actual revisiting of how we add metadata (and maybe use Search.gov as a teaching example for customers) so I'll create a backlog item for me to do a metadata audit & update. For now will merge this in for testing content!