Update app.py

app.py

@@ -69,7 +69,7 @@ LEADERBOARD_DF = get_leaderboard_df(EVAL_RESULTS_PATH, EVAL_REQUESTS_PATH, COLS,
 def init_leaderboard(dataframe):
     if dataframe is None or dataframe.empty:
         raise ValueError("Leaderboard DataFrame is empty or None.")
-    dataframe.insert(0, ' ', range(1, len(dataframe) + 1))
+    dataframe.insert(0, '', range(1, len(dataframe) + 1))
     return Leaderboard(
         value=dataframe,
         datatype=[c.type for c in fields(AutoEvalColumn)],