Deploy the site from a release branch moved on each published release (#207)

Co-authored-by: boratatouille <178141691+boratatouille@users.noreply.github.com>

.github/workflows/deploy-site.yml

@@ -0,0 +1,33 @@
+name: Deploy site on release
+
+# Cloudflare Workers Builds deploys the site from the `release` branch.
+# Publishing a GitHub release moves `release` to the released tag.
+
+on:
+  release:
+    types: [published]
+  workflow_dispatch:
+    inputs:
+      tag:
+        description: Tag to deploy (for example 1.1.0)
+        required: true
+        type: string
+
+permissions:
+  contents: write
+
+jobs:
+  move-release-branch:
+    runs-on: ubuntu-latest
+    if: github.event_name == 'workflow_dispatch' || github.event.release.prerelease == false
+    steps:
+      - uses: actions/checkout@v4
+        with:
+          fetch-depth: 0
+
+      - name: Point release branch at tag
+        env:
+          TAG: ${{ inputs.tag || github.event.release.tag_name }}
+        run: |
+          SHA=$(git rev-parse "refs/tags/$TAG^{commit}")
+          git push --force origin "$SHA:refs/heads/release"