Replace YAML keys from int to str

Replace YAML metadata integer keys with strings, as the Hub does not support integers.
See: https://github.com/huggingface/datasets/issues/5275

README.md

@@ -9,7 +9,6 @@ license:
 - unknown
 multilinguality:
 - monolingual
-pretty_name: Cats Vs. Dogs
 size_categories:
 - 10K<n<100K
 source_datasets:
@@ -19,6 +18,7 @@ task_categories:
 task_ids:
 - multi-class-image-classification
 paperswithcode_id: cats-vs-dogs
+pretty_name: Cats Vs. Dogs
 dataset_info:
   features:
   - name: image
@@ -27,8 +27,8 @@ dataset_info:
     dtype:
       class_label:
         names:
-          0: cat
-          1: dog
+          '0': cat
+          '1': dog
   splits:
   - name: train
     num_bytes: 4219400