ci: Add renovate-specific workflow

.github/workflows/generate-renovate-changelog.yaml

@@ -0,0 +1,68 @@
+name: "Charts: Update changelog for Renovate PR"
+
+concurrency: update-renovate-pr-changelog
+
+on:
+  push:
+    branches:
+#       - "renovate/**"
+      - "test/**"
+    paths:
+      - "charts/**"
+
+jobs:
+  update-changelog:
+    name: Update changelog
+    runs-on: ubuntu-20.04
+    steps:
+      - name: Checkout
+        uses: actions/checkout@v2
+        with:
+          fetch-depth: 2
+
+      - uses: dorny/paths-filter@v2
+        id: filter
+        with:
+          base: ${{ github.ref }}
+          list-files: shell
+          filters: |
+            addedOrModified:
+              - added|modified: 'charts/**'
+
+      - name: Run against changed charts
+        if: steps.filter.outputs.addedOrModified == 'true'
+        run: |
+          CHARTS=()
+          PATHS=(${{ steps.filter.outputs.addedOrModified_files }})
+          # Get only the chart paths
+          for i in "${PATHS[@]}"
+          do
+              IFS='/' read -r -a path_parts <<< "$i"
+              CHARTS+=("${path_parts[1]}/${path_parts[2]}")
+          done
+
+          # Remove duplicates
+          CHARTS=( `for i in ${CHARTS[@]}; do echo $i; done | sort -u` )
+
+          for i in "${CHARTS[@]}"
+          do
+              echo "Updating CHANGELOG for chart ${i}"
+              IFS='/' read -r -a chart_parts <<< "$i"
+              if [ -f "charts/${chart_parts[0]}"/"${chart_parts[1]}/Chart.yaml" ]; then
+                ./hack/renovate-releasenotes.sh "charts/${chart_parts[0]}"/"${chart_parts[1]}"
+              fi
+              echo ""
+              cat "charts/${chart_parts[0]}"/"${chart_parts[1]}/Chart.yaml"
+          done
+
+    # - name: Create commit
+    #   if: steps.filter.outputs.addedOrModified == 'true'
+    #   uses: stefanzweifel/git-auto-commit-action@v4
+    #   with:
+    #     push_options: --force
+    #     commit_message: Auto-generate chart README
+
+    #     commit_user_name: ${{ github.actor }}
+    #     commit_user_email: ${{ github.actor }}@users.noreply.github.com
+
+    #     file_pattern: charts/**/