fix deprecation notice

src/utils/misc.py

@@ -93,7 +93,7 @@ def exist_post(file_id: int) -> float | None:
 
 def time_now() -> float:
     """get current time based on timezone"""
-    now = datetime.utcnow()
+    now = datetime.now(datetime.timezone.utc)
     return (
         now.timestamp()
         + timezone(session[Config._session_timezone]).utcoffset(now).total_seconds()