Quote class label ids in YAML

We fixed a bug recently where datasets wouldn't use quote for class label ids. Now it does, in order to let the Hugging face Hub parse the YAML correctly.

README.md

@@ -18,8 +18,8 @@ dataset_info:
     dtype:
       class_label:
         names:
-          0: cat
-          1: dog
+          '0': cat
+          '1': dog
   splits:
   - name: train
     num_bytes: 166451650.0