Documentation update tool_calling: mapping back to function from response (vllm-project#20373)

Author: cronoik-inceptionai

docs/features/tool_calling.md

@@ -53,7 +53,7 @@ Next, make a request to the model that should result in it using the available t
     tool_call = response.choices[0].message.tool_calls[0].function
     print(f"Function called: {tool_call.name}")
     print(f"Arguments: {tool_call.arguments}")
-    print(f"Result: {get_weather(**json.loads(tool_call.arguments))}")
+    print(f"Result: {tool_functions[tool_call.name](**json.loads(tool_call.arguments))}")
     ```
 
 Example output: