fix narrativeqa name

metrics/longbench.py

@@ -70,7 +70,7 @@ Examples:
     {'exact_match': 33.3333, 'num_predicted': 3, 'mean_prediction_length_characters': 14.6667, 'longbench_score': 33.3333, 
     'display_keys': ['exact_match'], 'display': [33.3333]}
 
-    >>> longbench_metric = datasets.load_metric(longbench_metric_path, 'narrative_qa')  # 'narrative_qa' or "qasper"
+    >>> longbench_metric = datasets.load_metric(longbench_metric_path, 'narrativeqa')  # 'narrativeqa' or "qasper"
     >>> results = longbench_metric.compute(predictions=predictions, references=references)
     >>> print(results)
     {'f1': 72.2222, 'num_predicted': 3, 'mean_prediction_length_characters': 14.6667, 'longbench_score': 72.2222,