Properly close mistral response

sia/mistral_llm_engine.py

@@ -46,12 +46,12 @@ class MistralLlmEngine(LlmEngine):
         try:
             for chunk in stream_response:
                 if should_stop():
-                    stream_response.close()
+                    stream_response.response.close()
                     break
                 if content := chunk.data.choices[0].delta.content:
                     yield content
         finally:
-            stream_response.close()
+            stream_response.response.close()
 
     def token_count(self, system_prompt: str, main_context: str) -> int:
         messages = [