fix(ci): Helm chart was not automatically released

.github/workflows/helm-repo-index.yaml

@@ -0,0 +1,27 @@
+name: Helm repo index
+on: release
+jobs:
+  publish:
+    name: Publish helm repo index to gh-pages
+    runs-on: ubuntu-latest
+    steps:
+      - name: Checkout
+        uses: actions/checkout@v1
+
+      - name: Generate index.yaml
+        uses: docker://quay.io/helmpack/chart-releaser:v1.0.0-beta.1
+        run: |
+          mkdir .helm-index
+          cr index \
+            --charts-repo https://apricote.github.io/Listory
+            --package-path charts
+            --owner owner
+            --git-repo Listory
+            --index-path .helm-index/index.yaml
+
+      - name: Publish to gh-pages
+        uses: JamesIves/github-pages-deploy-action@releases/v3
+        with:
+          ACCESS_TOKEN: ${{ secrets.GITHUB_TOKEN }}
+          BRANCH: gh-pages # The branch the action should deploy to.
+          FOLDER: .helm-index # The folder the action should deploy.