feat(ci): enforce README update on major update (#1341)

.github/workflows/validate-pullrequest.yaml

@@ -38,6 +38,8 @@ jobs:
     name: Validate Title
     runs-on: ubuntu-latest
     needs: getChangedChart
+    permissions:
+      pull-requests: read
     env:
       PR_TITLE: ${{ github.event.pull_request.title }}
     steps:
@@ -66,3 +68,17 @@ jobs:
             echo "PR title must have scope '$CHANGED_CHART/\$subscope'" >&2
             exit 1
           fi
+      - name: Verify readme is updated on major update
+        if: ${{ needs.getChangedChart.outputs.found == 'true' }}
+        env:
+          CHANGED_CHART: ${{ needs.getChangedChart.outputs.chart }}
+        run: |
+          set -e
+          set -o pipefail
+
+          if cog verify "$PR_TITLE" 2>&1 | grep -qi 'BREAKING CHANGE'; then
+            if ! gh api --paginate "/repos/${GITHUB_REPOSITORY}/pulls/${PULL_REQUEST_NUMBER}/files" | jq -cr 'map(.filename)[]' | grep -qi "charts/$CHANGED_CHART/README.md.gotmpl"; then
+              echo "You need to update the readme on a major update" >&2
+              exit 1
+            fi
+          fi