Update app.py

change to chatgpt

app.py

@@ -185,7 +185,7 @@ if __name__ == "__main__":
                     large_language_model = gr.Dropdown(
                         list(llm_model_dict.keys()),
                         label="large language model",
-                        value="ChatGLM-6B-int4")
+                        value="ChatGPT")
 
                     embedding_model = gr.Dropdown(list(
                         embedding_model_dict.keys()),