Add a test coverage on label smoothing summations

Author: (Ian Stenbit)

keras_cv/layers/preprocessing/cut_mix_test.py

@@ -44,6 +44,7 @@ def test_label_smoothing(self):
         layer = CutMix(1.0, label_smoothing=0.2, seed=1)
         xs, ys = layer(xs, ys)
         self.assertNotAllClose(ys, 0.0)
+        self.assertAllClose(tf.math.reduce_sum(ys, axis=-1), (1.0, 1.0))
 
     def test_cut_mix_call_results(self):
         xs = tf.cast(

keras_cv/layers/preprocessing/mix_up_test.py

@@ -44,6 +44,7 @@ def test_label_smoothing(self):
         layer = MixUp(1.0, label_smoothing=0.2)
         xs, ys = layer(xs, ys)
         self.assertNotAllClose(ys, 0.0)
+        self.assertAllClose(tf.math.reduce_sum(ys, axis=-1), (1.0, 1.0))
 
     def test_mix_up_call_results(self):
         xs = tf.cast(