added action to comment on release pr (#577)

Author: chatton

.github/workflows/create-release-pr.yml

@@ -31,3 +31,6 @@ jobs:
           # include date in the pr branch name to ensure duplicate branches to not get created.
           PR_BRANCH_NAME: 'release-v${{steps.release_version.outputs.OUTPUT}}-${{ steps.release_version.outputs.DATE }}'
           PR_TITLE: 'Release MongoDB Kubernetes Operator v${{ steps.release_version.outputs.OUTPUT }}'
+
+          # Note: sonar github is a repo scoped token, which allows this action to trigger other actions.
+          GITHUB_TOKEN: ${{ secrets.SONAR_GITHUB_TOKEN }}

.github/workflows/release-images.yml

@@ -90,3 +90,25 @@ jobs:
         bodyFile: "${{ github.workspace }}/docs/RELEASE_NOTES.md"
         draft: true
         token: ${{ secrets.GITHUB_TOKEN }}
+
+  comment:
+    runs-on: ubuntu-latest
+    needs: [merge-release-pr-and-draft-github-release]
+    steps:
+      - name: Checkout Code
+        uses: actions/checkout@v2
+      - name: Determine Release Version
+        id: release_version
+        run: |
+          VERSION=$(jq -r '."mongodb-kubernetes-operator"' < $GITHUB_WORKSPACE/release.json)
+          echo "::set-output name=version::${VERSION}"
+      - uses: actions/github-script@v3
+        with:
+          github-token: ${{secrets.GITHUB_TOKEN}}
+          script: |
+            github.issues.createComment({
+              issue_number: context.issue.number,
+              owner: context.repo.owner,
+              repo: context.repo.repo,
+              body: 'Review and publish the release here: https://github.com/mongodb/mongodb-kubernetes-operator/releases/tag/v${{ steps.release_version.outputs.version }}'
+            })