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

@@ -62,12 +62,12 @@ dataset_info:
     - name: tokens
       sequence: string
   splits:
-  - name: test
-    num_bytes: 2911702563
-    num_examples: 10557
   - name: train
     num_bytes: 9115940054
     num_examples: 32747
+  - name: test
+    num_bytes: 2911702563
+    num_examples: 10557
   - name: validation
     num_bytes: 968994186
     num_examples: 3461