Update assign-milestone-on-close.yml

.github/workflows/assign-milestone-on-close.yml

@@ -17,6 +17,15 @@ jobs:
   assign-milestone:
     runs-on: ubuntu-latest
     steps:
+      - name: Get payload content
+        id: payload-content
+        uses: actions/github-script@v7
+        with:
+          script: return json.stringify(context.payload);
+          result-encoding: string
+      - name: Print payload content
+        id: print-payload
+        run: echo "${{steps.get-payload.outputs.result}}"
       - name: Check if milestone is set
         id: check-milestone
         uses: actions/github-script@v7