Update app.py

app.py

@@ -202,7 +202,7 @@ def certification(hf_username):
       case "demo":
         u7_usernames = hf_hub_download(USERNAMES_DATASET_ID, repo_type = "dataset", filename="usernames.csv", token=HF_TOKEN)
         u7_users = pd.read_csv(u7_usernames)
-        if hf_username in u7_users['username']:
+        if hf_username in u7_users['username'].tolist():
             unit["best_result"] = 0
             unit["best_model_id"] = "Demo check passed, no model id"
             unit["passed_"] = True