Update task category to video-text-to-text

The existing task category `visual-question-answering` is changed to `video-text-to-text` to more accurately reflect the kind of dataset.

README.md

@@ -1,20 +1,20 @@
 ---
+language:
+- en
+license: apache-2.0
+size_categories:
+- 1K<n<10K
+task_categories:
+- video-text-to-text
+pretty_name: lsdbench
 configs:
 - config_name: default
   data_files:
   - split: test
     path: mc_qa_annotations_1300.json
-license: apache-2.0
-task_categories:
-- visual-question-answering
-language:
-- en
 tags:
 - video
 - text
-pretty_name: lsdbench
-size_categories:
-- 1K<n<10K
 ---
 
 # Dataset Card for LSDBench: Long-video Sampling Dilemma Benchmark