Update summary

Author: lizekai-richard

doc/SUMMARY.md

@@ -22,4 +22,9 @@
     - [VGG](models/vgg.md)
     - [MLP](models/mlp.md)
 
-- [Datasets](datasets/overview.md)
+- [Datasets](datasets/overview.md)
+
+- [Augmentations](augmentations/overview.md)
+    - [DSA](augmentations/dsa.md)
+    - [CutMix](augmentations/cutmix.md)
+    - [Mixup](augmentations/mixup.md)