ruff ci

src/schedule/schedule_manager.py

@@ -1,7 +1,6 @@
 import orjson
 import asyncio
-import random
-from datetime import datetime, time, timedelta, date
+from datetime import datetime, time, timedelta
 from typing import Optional, List, Dict, Any, TYPE_CHECKING
 from lunar_python import Lunar
 from pydantic import BaseModel, ValidationError, validator