This is no longer in beta https://docs.github.com/en/pages/getting-started-with-github-pages/using-custom-workflows-with-github-pages. Example: https://github.com/JuliaPluto/Pinot.jl/blob/5568f535d0ca04f7c4681ae9b0e5a1554559f339/.github/workflows/Test.yml#L50-L56
