[CHORE]: x: T = None to x: Optional[T] = None (#24217)

api/tests/integration_tests/vdb/__mock/baiduvectordb.py

@@ -1,5 +1,6 @@
 import os
 from collections import UserDict
+from typing import Optional
 from unittest.mock import MagicMock
 
 import pytest
@@ -21,7 +22,7 @@ class MockBaiduVectorDBClass:
     def mock_vector_db_client(
         self,
         config=None,
-        adapter: HTTPAdapter = None,
+        adapter: Optional[HTTPAdapter] = None,
     ):
         self.conn = MagicMock()
         self._config = MagicMock()