Update datasets task tags to align tags with models (#4067)

* update tasks list

* update tags in dataset cards

* more cards updates

* update dataset tags parser

* fix multi-choice-qa

* style

* small improvements in some dataset cards

* allow certain tag fields to be empty

* update vision datasets tags

* use multi-class-image-classification and remove other tags

Commit from https://github.com/huggingface/datasets/commit/edb4411d4e884690b8b328dba4360dbda6b3cbc8

README.md

@@ -15,10 +15,12 @@ size_categories:
 source_datasets:
 - original
 task_categories:
-- sequence-modeling
+- text-generation
+- fill-mask
 - text-classification
 task_ids:
 - language-modeling
+- masked-language-modeling
 - sentiment-classification
 paperswithcode_id: dbrd
 ---
@@ -63,7 +65,7 @@ The DBRD (pronounced *dee-bird*) dataset contains over 110k book reviews of whic
 
 ### Supported Tasks and Leaderboards
 
-- `sequence-modeling`: The dataset can be used to train a model for sequence modeling, more specifically language modeling.
+- `text-generation`: The dataset can be used to train a model for sequence modeling, more specifically language modeling.
 - `text-classification`: The dataset can be used to train a model for text classification, more specifically sentiment classification, using the provided positive/negative sentiment polarity labels.
 
 ### Languages