Add CI workflow to deploy to GitHub pages on merges to main

- `withastro/action` is the primary mechanism that builds dist/
   from source and deploys to GitHub pages

Signed-off-by: Dan Childers <dchilder@redhat.com>

Author: danchild

.github/workflows/deploy.yml

@@ -0,0 +1,33 @@
+name: Deploy to GitHub Pages
+
+on:
+  push:
+    branches: [main]
+
+permissions:
+  contents: read
+  pages: write
+  id-token: write
+
+concurrency:
+  group: pages
+  cancel-in-progress: false
+
+jobs:
+  build:
+    name: Build
+    runs-on: ubuntu-latest
+    steps:
+      - uses: actions/checkout@v4
+      - uses: withastro/action@v6
+
+  deploy:
+    name: Deploy
+    needs: build
+    runs-on: ubuntu-latest
+    environment:
+      name: github-pages
+      url: ${{ steps.deployment.outputs.page_url }}
+    steps:
+      - id: deployment
+        uses: actions/deploy-pages@v4