Provide the names of podcasts in the art category in 2018.
art category refers to category = 'arts'; in 2018 refers to created_at like '2018%'; name of podcast refers to title
SELECT DISTINCT T2.title FROM categories AS T1 INNER JOIN reviews AS T2 ON T2.podcast_id = T1.podcast_id WHERE T1.category = 'arts' AND T2.created_at LIKE '2018-%'