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

@@ -44,15 +44,15 @@ dataset_info:
           12: I-product
   config_name: wnut_17
   splits:
-  - name: test
-    num_bytes: 405536
-    num_examples: 1287
   - name: train
     num_bytes: 1078379
     num_examples: 3394
   - name: validation
     num_bytes: 259383
     num_examples: 1009
+  - name: test
+    num_bytes: 405536
+    num_examples: 1287
   download_size: 800955
   dataset_size: 1743298
 ---