doc: Added a github workflow which automatically builds and deploys the documentation to the github pages webserver

from now on, any change to the 'site' branch will trigger a rebuild/deploy action.

Author: rhornig

.github/workflows/sphinx-doc-build-deploy.yml

@@ -0,0 +1,55 @@
+# Workflow for building and deploying a Sphinx site to GitHub Pages
+name: Build and deploy sphinx docs to GitHub Pages from site branch
+
+on:
+  # Runs on pushes targeting the default branch
+  push:
+    branches: ["deployed-website"]
+
+  # Allows you to run this workflow manually from the Actions tab
+  workflow_dispatch:
+
+# Sets permissions of the GITHUB_TOKEN to allow deployment to GitHub Pages
+permissions:
+  contents: read
+  pages: write
+  id-token: write
+
+# Allow only one concurrent deployment, skipping runs queued between the run in-progress and latest queued.
+# However, do NOT cancel in-progress runs as we want to allow these production deployments to complete.
+concurrency:
+  group: "pages"
+  cancel-in-progress: false
+
+jobs:
+  # Build job
+  build:
+    runs-on: ubuntu-latest
+    steps:
+      - name: Checkout
+        uses: actions/checkout@v4
+      - name: Setup Pages
+        uses: actions/configure-pages@v4
+      - name: Sphinx Build
+        uses: ammaraskar/sphinx-action@7.1.2
+        with:
+          docs-folder: doc/src
+          build-command: make html
+          # Run before the build command, you can use this to install system level dependencies, for example with "apt-get update -y && apt-get install -y perl"
+          pre-build-command: doc/src/tools/setup-build-process.sh
+      - name: Upload github pages artifact
+        uses: actions/upload-pages-artifact@v3
+        with:
+          path: "doc/src/_build/html/"
+
+  # Deployment job
+  deploy:
+    environment:
+      name: github-pages
+      url: ${{ steps.deployment.outputs.page_url }}
+    runs-on: ubuntu-latest
+    needs: build
+    steps:
+      - name: Deploy uploaded artifact to GitHub Pages
+        id: deployment
+        uses: actions/deploy-pages@v4

doc/src/tools/setup-build-process.sh

@@ -0,0 +1,8 @@
+#!/bin/sh
+
+export DEBIAN_FRONTEND=noninteractive
+apt-get update -yy
+apt-get upgrade -yy
+apt-get install -yy git
+git config --global --add safe.directory /github/workspace
+pip3 install sphinx-immaterial doxysphinx