exiarepairii

In [Line 103 of input_pipeline_tf2_or_jax.py](https://github.com/google-research/big_transfer/blob/49afe42338b62af9fbe18f0258197a33ee578a6b/input_pipeline_tf2_or_jax.py#L103), why use `tf.image.flip_left_right` instead of `tf.image.random_flip_left_right`? From [tensorflow's doc](https://www.tensorflow.org/api_docs/python/tf/image/flip_left_right), `tf.image.flip_left_right` will always flip the image, without any randomness. It makes more sense to use `tf.image.random_flip_left_right`...