Admin interface keyboard focus invisible for site name links on Sites page

[svenaas]

When navigating by keyboard (on Chrome/Mac), on the /sites page in particular something prevents the visual indication from appearing when a site name link (e.g. "18f/18f.gsa.gov") has focus. I haven't seen this problem elsewhere on the site, and it could stand to be improved. This doesn't present a barrier when a screenreader is the primary output device, but for a sighted keyboard user it isn't great.

Example of this problem:

The "18f/18f.gsa.gov" link is focused here following tab navigation, with no visual indication of focus (in this case the link has been visited, but the same thing occurs with unvisited site links).

Example of normal focus display:

The "LIVE" link is focused here following tab-navigation, with normal focus indicated:

Notes

• Found during cloud-gov/product#2497 which was a spot check survey and not a thorough review of all pages and components; there may be additional issues.

Acceptance Criteria

• [ ] When tabbing into /sites and bringing focus to a site name (e.g. "18f/18f.gsa.gov") the same visual indicator should be present as when focusing other links.