Add task category

This PR adds the `image-text-to-text` task category to the dataset card.

README.md

@@ -25,7 +25,11 @@ dataset_info:
     num_examples: 60
   download_size: 5231483
   dataset_size: 16595970.0
+task_categories:
+- image-text-to-text
 ---
+
+```markdown
 # Clock and Calendar Dataset
 
 ## Overview
@@ -79,3 +83,4 @@ The Calendar dataset contains images of yearly calendars with questions related
 
 ## Acknowledgments
 This dataset was compiled for research and development purposes.
+```