fixed flake8 lint errors

pyserve/ctl/state/__init__.py

@@ -9,9 +9,7 @@ import os
 import time
 from dataclasses import asdict, dataclass, field
 from pathlib import Path
-from typing import Any, Dict, List, Optional
-
-import yaml
+from typing import Any, Dict, Optional
 
 
 @dataclass