Update data_augmentation.md

docs/zh_CN/training/config_description/data_augmentation.md

@@ -592,6 +592,7 @@ Mixup 是最先提出的图像混叠增广方案，其原理简单、方便实
             mean: [0.485, 0.456, 0.406]
             std: [0.229, 0.224, 0.225]
             order: ''
+      batch_transform_ops:
         - OpSampler:
             MixupOperator:
               alpha: 0.8