Leon Bridges.In the last two weeks, the Grammy-winning R&B artist has attended the Met Gala, appeared on “The Late Show With Stephen Colbert” and performed his song “River” with Jon Batiste during the In Memoriam tribute at the Emmys.And on Friday, Bridges, 32, will take the main stage during this weekend’s 10th-anniversary edition of the Governors Ball music festival at Citi Field.