tests: adds aXe test for `<Officers />`; resolves `key` bug

[mattxwang]

Followup to #412, gradually increasing coverage.

Two small notes:

1. You need to mock next/image somehow. This trivial mock is from https://github.com/vercel/next.js/discussions/18516, however I think after you upgrade to Next 12 it becomes easier.
2. There's a current bug in Officers that incorrectly uses a non-existent field as the key. Updated to use an existing field.

[mattxwang]

Just going through my own stale PRs, bump @matthewcn56.