fixed typo

app.py

@@ -210,7 +210,7 @@ def pick_best_review(feedback_list, agent_prompt, review, pdf_text, model):
         "Authorization": f"Bearer {openai_api_key}"
         }
         payload = {
-        "model": "gpt-4o-mini	,
+        "model": "gpt-4o-mini",
         "messages": messages,
         "max_tokens": 1000,
         "temperature": 0.2