Fix input parameter type

pr_auc.py

@@ -72,8 +72,8 @@ class PRAUC(evaluate.Metric):
             inputs_description=_KWARGS_DESCRIPTION,
             # This defines the format of each prediction and reference
             features=datasets.Features({
-                'prediction_scores': datasets.Sequence(datasets.Value("float")),
-                'references': datasets.Value('int64'),
+                'prediction_scores': datasets.Value("float"),
+                'references': datasets.Value('int32'),
             }),
             # Homepage of the module for documentation
             homepage="http://module.homepage",