Add GitHub Pages deployment job

.github/workflows/pages.yml

@@ -0,0 +1,60 @@
+name: Deploy to Pages
+
+on:
+  # Runs on pushes targeting the default branch
+  push:
+    branches: ['source']
+
+  # 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@v3
+      - name: Setup Ruby
+        uses: ruby/setup-ruby@v1
+        with:
+          ruby-version: '2.7'
+          bundler-cache: true
+      - name: Setup Node
+        uses: actions/setup-node@v3
+        with:
+          node-version: '18'
+          cache: 'npm'
+      - name: Setup Pages
+        id: pages
+        uses: actions/configure-pages@v3
+      - name: Build
+        run: bundle exec middleman build
+      - name: Upload artifact
+        uses: actions/upload-pages-artifact@v2
+        with:
+          path: build
+
+  # Deployment job
+  deploy:
+    environment:
+      name: github-pages
+      url: ${{ steps.deployment.outputs.page_url }}
+    runs-on: ubuntu-latest
+    needs: build
+    steps:
+      - name: Deploy to GitHub Pages
+        id: deployment
+        uses: actions/deploy-pages@v2