Use new native GitHub Pages deployment

Author: fregante

.github/workflows/demo.yml

@@ -1,21 +1,40 @@
+# From https://github.blog/changelog/2022-07-27-github-pages-custom-github-actions-workflows-beta/
 name: Demo
 
 on:
   - pull_request
   - push
 
+# 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:
+  build:
     runs-on: ubuntu-latest
     steps:
       - uses: actions/checkout@v3
-      - run: npm install
+      - run: npm ci
       - run: npm run demo:build
       - run: npm run demo:test
-      - uses: peaceiris/actions-gh-pages@v3
-        if: github.ref == 'refs/heads/main'
-        with:
-          github_token: ${{ secrets.GITHUB_TOKEN }}
-          publish_dir: ./demo/dist
-          user_name: 'github-actions[bot]'
-          user_email: 'github-actions[bot]@users.noreply.github.com'
+      - name: Upload artifact
+        uses: actions/upload-pages-artifact@v1
+
+  deploy:
+    environment:
+      name: github-pages
+      url: ${{ steps.deployment.outputs.page_url }}
+    runs-on: ubuntu-latest
+    needs: build
+    if: github.ref == 'refs/heads/main'
+    steps:
+      - name: Deploy to GitHub Pages
+        id: deployment
+        uses: actions/deploy-pages@v1