Fix for openai multi tools input format. (#14653)

Sometimes, the tool_schema is like:
  
` {'action_name': 'search_items', 'action': {'term': 'pizza'}}`

sometimes, specially with gpt3.5 it comes like:

`{'action_name': 'search_items', 'term': 'pizza'}`

and it fails.

This PR is a way to make it work in both scenarios.

issues releated: #6624 

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Co-authored-by: Lucca Zenobio <lucca.zenobio@ifood.com.br>

libs/langchain/langchain/agents/openai_functions_multi_agent/base.py

@@ -58,7 +58,12 @@ def _parse_ai_message(message: BaseMessage) -> Union[List[AgentAction], AgentFin
 
         final_tools: List[AgentAction] = []
         for tool_schema in tools:
-            _tool_input = tool_schema["action"]
+            if "action" in tool_schema:
+                _tool_input = tool_schema["action"]
+            else:
+                # drop action_name from schema
+                _tool_input = tool_schema.copy()
+                del _tool_input["action_name"]
             function_name = tool_schema["action_name"]
 
             # HACK HACK HACK: