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

@@ -36,15 +36,15 @@ dataset_info:
   - name: answerKey
     dtype: string
   splits:
-  - name: test
-    num_bytes: 258017
-    num_examples: 1140
   - name: train
     num_bytes: 2209044
     num_examples: 9741
   - name: validation
     num_bytes: 274033
     num_examples: 1221
+  - name: test
+    num_bytes: 258017
+    num_examples: 1140
   download_size: 4680691
   dataset_size: 2741094
 ---