's season 21 finale will feature some star-studded performances!In addition to the Top 5 competitors — Girl Named Tom, Jershika Maple, Paris Winningham, Wendy Moten and Hailey Mia — performing alongside their coaches, Blake Shelton, Kelly Clarkson and John Legend, NBC has also announced on a whole host of A-list stars who will be taking the stage during next Tuesday's live, two-hour finale.First-time coach Ariana Grande will perform with Kid Cudi, as the pair debut the first live performance of