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

@@ -37,23 +37,23 @@ dataset_info:
     dtype:
       class_label:
         names:
-          0: 'Yes'
-          1: 'No'
-          2: In the middle, neither yes nor no
-          3: Probably yes / sometimes yes
-          4: Probably no
-          5: Yes, subject to some conditions
-          6: Other
-          7: I am not sure how X will interpret Y’s answer
+          '0': 'Yes'
+          '1': 'No'
+          '2': In the middle, neither yes nor no
+          '3': Probably yes / sometimes yes
+          '4': Probably no
+          '5': Yes, subject to some conditions
+          '6': Other
+          '7': I am not sure how X will interpret Y’s answer
   - name: goldstandard2
     dtype:
       class_label:
         names:
-          0: 'Yes'
-          1: 'No'
-          2: In the middle, neither yes nor no
-          3: Yes, subject to some conditions
-          4: Other
+          '0': 'Yes'
+          '1': 'No'
+          '2': In the middle, neither yes nor no
+          '3': Yes, subject to some conditions
+          '4': Other
   splits:
   - name: train
     num_bytes: 8149489