message: Update image.py
  Replaced np_utils with utils, as np_utils is removed in TF 2.x
diff: @@ -661,8 +661,8 @@ class ImageDataGenerator(image.ImageDataGenerator):
  ```python
  (x_train, y_train), (x_test, y_test) = cifar10.load_data()
  - y_train = np_utils.to_categorical(y_train, num_classes)
  - y_test = np_utils.to_categorical(y_test, num_classes)
  + y_train = utils.to_categorical(y_train, num_classes)
  + y_test = utils.to_categorical(y_test, num_classes)
  datagen = ImageDataGenerator(
  featurewise_center=True,
  featurewise_std_normalization=True,
  