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

@@ -35,12 +35,12 @@ dataset_info:
   - name: target_text
     dtype: string
   splits:
-  - name: test
-    num_bytes: 77264695
-    num_examples: 72831
   - name: train
     num_bytes: 619269257
     num_examples: 582659
+  - name: test
+    num_bytes: 77264695
+    num_examples: 72831
   - name: val
     num_bytes: 77335069
     num_examples: 72831