Publishing to GitHub Pages using GitHub Actions

Adds a section under the `Publish to GitHub Pages` with an example on how to use GitHub Actions to publish an Antora site
3 jobs for patch-2 in 4 minutes and 11 seconds (queued for 3 seconds)
latest
Status Job ID Name Coverage
  Init
passed #806643870
yarn

00:01:10

 
  Verify
passed #806643880
lint

00:01:20

passed #806643887
test

00:03:00