Reorder split names

Reorder split names in the YAML metadata to be aligned with the order in the loading script.
See: https://github.com/huggingface/datasets/issues/5258

README.md

@@ -44,12 +44,12 @@ dataset_info:
  - name: topic
  dtype: string
  splits:
- - name: test
- num_bytes: 6607134
- num_examples: 17705
  - name: train
  num_bytes: 17619123
  num_examples: 45640
+ - name: test
+ num_bytes: 6607134
+ num_examples: 17705
  - name: validation
  num_bytes: 1505979
  num_examples: 3926