All GitHub Pages Themes should get Google Lighthouse Scores of 100

[mgifford]

These default themes should follow best practices. Minima falls short.

[ashmaroli]

Hello @mgifford, the Minima demo site currently has an Accessibility score of 95 on desktop (had to deploy a fresh build to refresh stylesheets). Hope that is acceptable for you.
The missing 5 points is for the theme-switcher element which is a demo-site-only feature. So, not so keen on improving that.