Rename config override tests to reflect multiple-field behavior and erase unnecessary comment

Author: TadakiAsechi

tests/client/test_base_client.py

@@ -129,7 +129,7 @@ async def test_send_message_non_streaming_agent_capability_false(
 
 
 @pytest.mark.asyncio
-async def test_send_message_callsite_config_overrides_history_length_non_streaming(
+async def test_send_message_callsite_config_overrides_multiple_fields_non_streaming(
     base_client: BaseClient, mock_transport: MagicMock, sample_message: Message
 ):
     base_client._config.streaming = False
@@ -139,7 +139,6 @@ async def test_send_message_callsite_config_overrides_history_length_non_streami
         status=TaskStatus(state=TaskState.completed),
     )
 
-    # history_length だけでなく、複数フィールドを明示的に上書き
     cfg = MessageSendConfiguration(
         history_length=2,
         blocking=False,
@@ -165,7 +164,7 @@ async def test_send_message_callsite_config_overrides_history_length_non_streami
 
 
 @pytest.mark.asyncio
-async def test_send_message_callsite_config_overrides_history_length_streaming(
+async def test_send_message_callsite_config_overrides_multiple_fields_streaming(
     base_client: BaseClient, mock_transport: MagicMock, sample_message: Message
 ):
     base_client._config.streaming = True