Fix release workflow: sync main to gh-pages and deploy from gh-pages branch

.github/workflows/release.yml

@@ -15,14 +15,23 @@ concurrency:
   cancel-in-progress: true
 
 jobs:
+  sync:
+    name: Sync Main to GH-Pages
+    uses: ./.github/workflows/sync-gh-pages.yml
+    permissions:
+      contents: write
+
   deploy:
     name: Deploy Site To GitHub Pages
+    needs: sync
     runs-on: ubuntu-latest
     environment:
       name: github-pages
       url: ${{ steps.deployment.outputs.page_url }}
     steps:
       - uses: actions/checkout@v4
+        with:
+          ref: ${{ needs.sync.outputs.synced_sha }}
       - uses: actions/setup-node@v4
         with:
           node-version: 20
@@ -38,7 +47,7 @@ jobs:
         run: |
           npm test
       - name: Upload Pages artifact
-        uses: actions/upload-pages-artifact@v3
+        uses: actions/upload-pages-artifact@v4
         with:
           path: ./website/build
       - name: Deploy to GitHub Pages

.github/workflows/sync-gh-pages.yml

@@ -0,0 +1,22 @@
+name: Sync Main to GH-Pages
+
+# Syncs the main branch to gh-pages so that the release workflow
+# can be triggered from gh-pages (required by environment protection rules).
+on:
+  workflow_dispatch:
+  workflow_call:
+
+permissions:
+  contents: write
+
+jobs:
+  sync:
+    name: Sync Main to GH-Pages Branch
+    runs-on: ubuntu-latest
+    steps:
+      - uses: actions/checkout@v4
+        with:
+          ref: main
+          fetch-depth: 0
+      - name: Push main to gh-pages
+        run: git push origin main:gh-pages --force-with-lease