Re-add the labeled event

.github/workflows/label-cherry-pick.yaml

@@ -3,6 +3,7 @@ name: Label Cherry Pick
 on:
   pull_request_target:
     types:
+      - labeled
       - closed
 
 jobs:
@@ -19,9 +20,16 @@ jobs:
       env:
         PR_LABELS: ${{ toJson(github.event.pull_request.labels) }}
         EVENT_ACTION: ${{ github.event.action }}
+        LABEL_NAME: ${{ github.event.label.name }}
         BASE_REF: ${{ github.base_ref }}
       run: |
-        labels=$(echo "$PR_LABELS" | jq -r '.[].name')
+        if [[ $EVENT_ACTION == 'closed' ]]; then
+          # Get a list of the labels from the PR.
+          labels=$(echo "$PR_LABELS" | jq -r '.[].name')
+        else
+          # Or get the label that was added on the merged PR.
+          labels=$LABEL_NAME
+        fi
 
         branches=("24.lts.1+" "23.lts.1+" "22.lts.1+" "21.lts.1+" "20.lts.1+" "19.lts.1+" "rc_11" "COBALT_9")
         filtered_branches=()