Extend lint test to test/ directory (#13247)

test/srt/experiment_runner.py

@@ -8,8 +8,7 @@ import threading
 import time
 from dataclasses import dataclass
 from datetime import datetime
-from pathlib import Path
-from typing import Dict, List, Optional, Tuple
+from typing import List, Optional, Tuple
 
 import psutil
 import requests