Align more metadata with other repo types (models,spaces) (#4607)

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

Fix typo in train split name (#3751)

Update files from the datasets library (from 1.18.0)

Update files from the datasets library (from 1.7.0)

Update files from the datasets library (from 1.3.0)

Update files from the datasets library (from 1.2.0)