Update app.py

app.py

@@ -591,7 +591,7 @@ if __name__ == "__main__":
     logger.info(f"args: {args}")
 
     model_path = "liuhaotian/llava-v1.5-13b"
-    bits = os.getenv("bits", 8)
+    bits = int(os.getenv("bits", 8))
 
     preload_models(model_path)