Those behind this year’s Kennedy Center Honors have found what they’re looking for in Irish rockers U2 and four other artists. The band will join actor and filmmaker George Clooney, soul and R&B singer Gladys Knight, Christian pop artist Amy Grant and the Cuban-born American composer Tania Leon this December in being honored at the annual celebration, the John F. Kennedy Center for the Performing Arts announced Thursday. Now in its 45 year, the event toasts honorees for their contributions to American culture through various performing arts, from music, dance, theater and opera to film and TV….