!9883 Fixbug: rise example bug and benchmarkder=() exectuable

From: @lixiaohui33
Reviewed-by: @wuxuejian,@jonyguo,@lilongfei15
Signed-off-by: @lilongfei15

mindspore/explainer/_image_classification_runner.py

@@ -167,7 +167,7 @@ class ImageClassificationRunner:
         if not explainers:
             raise ValueError("Argument explainers is empty.")
 
-        if benchmarkers:
+        if benchmarkers is not None:
             check_value_type("benchmarkers", benchmarkers, list)
             if not all(isinstance(ele, AttributionMetric) for ele in benchmarkers):
                 raise TypeError("Argument benchmarkers is not list of mindspore.explainer.benchmark .")

mindspore/explainer/explanation/_attribution/_perturbation/rise.py

@@ -77,7 +77,7 @@ class RISE(PerturbationAttribution):
         >>> targets = 5
         >>> saliency = rise(inputs, targets)
         >>> # `targets` can also be a 2D tensor
-        >>> targets = ms.Tensor([[5], [1]])
+        >>> targets = ms.Tensor([[5], [1]], ms.int32)
         >>> saliency = rise(inputs, targets)
 """