docs: replace initialize_agent with create_react_agent in searchapi - replace deprecated load_tools (#31203)

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Author: MichaelLi65535

docs/docs/integrations/providers/searchapi.mdx

@@ -73,7 +73,7 @@ You can also easily load this wrapper as a Tool (to use with an Agent).
 You can do this with:
 
 ```python
-from langchain.agents import load_tools
+from langchain_community.agent_toolkits.load_tools import load_tools
 tools = load_tools(["searchapi"])
 ```