remove unused imports

Author: davemssavage

tests/shared/test_session.py

@@ -9,9 +9,6 @@
 from mcp.shared.exceptions import McpError
 from mcp.shared.memory import create_connected_server_and_client_session
 from mcp.types import (
-    CancelledNotification,
-    CancelledNotificationParams,
-    ClientNotification,
     ClientRequest,
     EmptyResult,
 )