Add run-cloverage tag to run Cloverage on non-master branches (#38732)

.github/workflows/backend.yml

@@ -6,7 +6,7 @@ on:
       - "master"
       - "release-**"
   pull_request:
-    types: [opened, synchronize, reopened, ready_for_review]
+    types: [opened, synchronize, reopened, ready_for_review, labeled]
 
 concurrency:
   group: ${{ github.workflow }}-${{ github.head_ref && github.ref || github.run_id }}
@@ -65,7 +65,8 @@ jobs:
 
   be-linter-cloverage:
     needs: files-changed
-    if: github.ref_name == 'master' && needs.files-changed.outputs.backend_all == 'true'
+    if: (github.ref_name == 'master' && needs.files-changed.outputs.backend_all == 'true')
+        || contains(github.event.pull_request.labels.*.name, 'run-cloverage')
     runs-on: ubuntu-22.04
     timeout-minutes: 90
     steps: