chore(graph_engine): Use XXX | None instead of Optional[XXX]

api/core/workflow/graph_engine/command_channels/redis_channel.py

@@ -7,7 +7,7 @@ Each instance uses a unique key for its command queue.
 """
 
 import json
-from typing import TYPE_CHECKING, Optional
+from typing import TYPE_CHECKING
 
 from ..entities.commands import AbortCommand, CommandType, GraphEngineCommand
 
@@ -86,7 +86,7 @@ class RedisChannel:
             pipe.expire(self._key, self._command_ttl)
             pipe.execute()
 
-    def _deserialize_command(self, data: dict) -> Optional[GraphEngineCommand]:
+    def _deserialize_command(self, data: dict) -> GraphEngineCommand | None:
         """
         Deserialize a command from dictionary data.