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

@@ -30,15 +30,15 @@ dataset_info:
   - name: text
     dtype: string
   splits:
-  - name: test
-    num_bytes: 40482864
-    num_examples: 100
   - name: train
     num_bytes: 11453688524
     num_examples: 28602
   - name: validation
     num_bytes: 17402307
     num_examples: 50
+  - name: test
+    num_bytes: 40482864
+    num_examples: 100
   download_size: 11740484131
   dataset_size: 11511573695
 ---