Change to ChatOpenAI

Author: piyushroshan

services/chatbot/src/chatbot_api.py

@@ -43,7 +43,7 @@ def load_global_retriever():
 
 
 def get_llm():
-    llm = ChatOpenAI(temperature=0.6, model_name="gpt-3.5-turbo-instruct")
+    llm = ChatOpenAI(temperature=0.6, model_name="gpt-3.5-turbo")
     return llm