Fix test_mcp_server_manager_config_integration_with_database cancellation error (#19801)

Mock _create_mcp_client to avoid network calls in health checks.
This prevents asyncio.CancelledError when the test teardown closes
the event loop while health checks are still pending.

The test focuses on conversion logic (access_groups, description)
not health check functionality, so mocking the network call is appropriate.

tests/mcp_tests/test_mcp_server.py

@@ -1105,9 +1105,16 @@ async def test_mcp_server_manager_config_integration_with_database():
 
     test_manager.get_allowed_mcp_servers = mock_get_allowed_servers
 
-    # Test the method (this tests our second fix)
-    import asyncio
+    # Mock _create_mcp_client to return a client that completes immediately
+    # This avoids network calls while preserving the actual conversion logic
+    def mock_create_mcp_client(*args, **kwargs):
+        mock_client = MagicMock()
+        mock_client.run_with_session = AsyncMock(return_value="ok")
+        return mock_client
+    
+    test_manager._create_mcp_client = mock_create_mcp_client
 
+    # Test the method (this tests our second fix)
     servers_list = await test_manager.get_all_mcp_servers_with_health_and_teams(
         user_api_key_auth=mock_user_auth
     )