workflow: change from circle-ci to github action for doc deployment

.github/workflows/build_documentation.yml

@@ -0,0 +1,55 @@
+name: Build and deploy documentation
+
+on:
+  push:
+    # Runs on pushes targeting the default branch
+    branches: [main]
+
+  # 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 one concurrent deployment
+concurrency:
+  group: "pages"
+  cancel-in-progress: true
+
+jobs:
+  deploy:
+    environment:
+      name: github-pages
+      url: ${{ steps.deployment.outputs.page_url }}
+    runs-on: ubuntu-latest
+    steps:
+      - name: Checkout
+        uses: actions/checkout@v3
+
+      - name: Setup pages
+        uses: actions/configure-pages@v3
+
+      - name: Install nix
+        uses: cachix/install-nix-action@v22
+        with:
+          nix_path: nixpkgs=channel:nixos-unstable
+
+      - name: Configure cachix
+        uses: cachix/cachix-action@v12
+        with:
+          name: nix-community
+          authToken: '${{ secrets.CACHIX_AUTH_TOKEN }}'
+
+      - run: nix build .#docs --show-trace
+
+      - name: Upload artifact
+        uses: actions/upload-pages-artifact@v2
+        with:
+          path: "result/share/doc"
+
+      - name: Deploy to GitHub Pages
+        id: deployment
+        uses: actions/deploy-pages@v2