remove commented blocks; fix parameter names

langchain-streamlit-demo/app.py

@@ -323,7 +323,7 @@ with sidebar:
 if provider_api_key:
  if st.session_state.provider == "OpenAI":
  st.session_state.llm = ChatOpenAI(
- model_name="test",
+ model_name=model,
  openai_api_key=provider_api_key,
  temperature=temperature,
  streaming=True,