[GH Actions] Create cherry-pick-label-check.yml (#1450)

The action fails if there is no cherry-pick-to- label applied to a PR.

.github/workflows/cherry-pick-label-check.yml

@@ -0,0 +1,22 @@
+name: Cherry Pick Label Check
+
+on:
+  pull_request:
+    types: 
+      - labeled
+      - unlabeled
+    branches:
+      - master
+
+jobs:
+  cherry-pick-label-check:
+    runs-on: ubuntu-latest
+
+    steps:
+      - name: Check labels
+        run: |
+            labels=$(jq -r '.pull_request.labels[].name' $GITHUB_EVENT_PATH)
+            if [[ ! $labels =~ ^cherry-pick-to- ]]; then
+                echo "No label starting with 'cherry-pick-to-' found."
+                exit 1
+            fi