fix error message for non logged in

app.py

@@ -15,7 +15,7 @@ from apscheduler.schedulers.background import BackgroundScheduler
 CONVERSION_SCRIPT = "convert_lora_to_gguf.py"
 
 def process_model(peft_model_id: str, q_method: str, private_repo, oauth_token: gr.OAuthToken | None):
-    if oauth_token.token is None:
+    if oauth_token is None or oauth_token.token is None:
         gr.Error("You must be logged in to use GGUF-my-lora")
         raise ValueError("You must be logged in to use GGUF-my-lora")
     model_name = peft_model_id.split('/')[-1]