Split website deployment into a separate action

.github/workflows/ci.yml

@@ -1,6 +1,10 @@
 name: alterschema
 on:
-  - push
+  push:
+    branches:
+      - master
+  pull_request:
+
 concurrency:
   group: ${{ github.ref }}
   cancel-in-progress: true
@@ -18,10 +22,6 @@ jobs:
     runs-on: ubuntu-20.04
     steps:
       - uses: actions/checkout@v3
+      - run: sudo apt update
       - run: sudo apt-get install --yes sassc
       - run: make www
-      - if: github.ref == 'refs/heads/master'
-        uses: peaceiris/actions-gh-pages@v3
-        with:
-          github_token: ${{ secrets.GITHUB_TOKEN }}
-          publish_dir: ./dist

.github/workflows/website-deploy.yml

@@ -0,0 +1,36 @@
+name: website
+on:
+  push:
+    branches: [ "master" ]
+  workflow_dispatch:
+
+permissions:
+  contents: read
+  pages: write
+  id-token: write
+
+concurrency:
+  group: website-deploy-${{ github.ref }}
+  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
+      - run: sudo apt update
+      - run: sudo apt-get install --yes sassc
+      - run: make www
+      - name: Setup Pages
+        uses: actions/configure-pages@v1
+      - name: Upload artifact
+        uses: actions/upload-pages-artifact@v1
+        with:
+          path: ./dist
+      - name: Deploy to GitHub Pages
+        id: deployment
+        uses: actions/deploy-pages@v2