ci: add conclusion job for protection rules (#1256)

Co-authored-by: Alexander Bayandin <[email protected]>

.github/workflows/e2e-test.yaml

@@ -268,3 +268,18 @@ jobs:
       - name: Cleanup
         if: always()
         run: make ${{ matrix.cluster }}-destroy
+
+  # This job simplifies setting branch protection rules (in GitHub UI)
+  # by allowing to set only this job instead of listing many others.
+  # It also makes it easier to rename or parametrise jobs (using matrix)
+  # which requires changes in branch protection rules
+  conclusion:
+    name: Conclusion
+    needs: [ e2e-tests ]
+    if: always()
+    runs-on: ubuntu-22.04
+    steps:
+      - name: Fail the job if any of the dependencies do not succeed or are skipped
+        run: exit 1
+        if: |
+          contains(needs.*.result, 'failed') || contains(needs.*.result, 'cancelled') || contains(needs.*.result, 'skipped')