Update agent_workflow.py

agent_workflow.py

@@ -3,7 +3,7 @@ import logging
 from typing import List, Dict, Any, Optional, Tuple, Callable, Union
 from dotenv import load_dotenv
 from llm_providers import LLMProvider
-from langchain.schema import HumanMessage
+from from langchain_core.messages import HumanMessage
 from tantivy_search_agent import TantivySearchAgent
 
 load_dotenv()