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

@@ -30,12 +30,12 @@ dataset_info:
   - name: qid
     dtype: string
   splits:
-  - name: test
-    num_bytes: 473730
-    num_examples: 1979
   - name: train
     num_bytes: 2770036
     num_examples: 10692
+  - name: test
+    num_bytes: 473730
+    num_examples: 1979
   - name: validation
     num_bytes: 295435
     num_examples: 1086