First deploy to GitHub Pages should be documented

[ivoputzer]

As of right now, it is not possible to trigger a GitHub Page deployment from inside a GitHub Workflow using the provided GITHUB_TOKEN secret. Workflows are required to use either a Deploy Key or a Personal Access Token to trigger the page build automatically while pushing changes to a given branch.

It "is possible" however to push changes to branches (ie. gh-pages) and trigger the deployment separately over HTTP when the Github Page has been deployed manually at least once.

git fetch --all
git checkout -t origin/gh-pages
git commit --allow-empty -m "first and only manual deployment"
git push -u origin gh-pages

Github is currently investigating on this issue https://github.community/t5/GitHub-Actions/Github-action-not-triggering-gh-pages-upon-push/m-p/26869