Update index.mdx

convert to chain

Author: Luke31

docs/platforms/python/integrations/langchain/index.mdx

@@ -81,8 +81,9 @@ import sentry_sdk
 sentry_sdk.init(...)  # same as above
 
 llm = ChatOpenAI(model="gpt-3.5-turbo-0125", temperature=0, api_key="bad API key")
-with sentry_sdk.start_transaction(op="ai-inference", name="The result of the AI inference"):
-    response = llm.invoke([("system", "What is the capital of France?")])
+  with sentry_sdk.start_transaction(op="ai-inference", name="The result of the AI inference"):
+    chain = (llm | StrOutputParser()).with_config({"run_name": "test-run"})
+    response = chain.invoke([("system", "What is the capital of France?")])
     print(response)
 ```