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

@@ -17,7 +17,6 @@ task_categories:
 - text-classification
 task_ids:
 - topic-classification
-paperswithcode_id: null
 pretty_name: Hausa Voa News Topic Classification Dataset (HausaVoaTopics)
 dataset_info:
   features:
@@ -27,11 +26,11 @@ dataset_info:
     dtype:
       class_label:
         names:
-          0: Africa
-          1: Health
-          2: Nigeria
-          3: Politics
-          4: World
+          '0': Africa
+          '1': Health
+          '2': Nigeria
+          '3': Politics
+          '4': World
   splits:
   - name: train
     num_bytes: 144932