The Country Music Association announced four collaborative performances set to take the stage at the 51st CMA Awards on Nov. 8. The pairings include: Kelsea Ballerini and Reba McEntire Dierks Bentley and Rascal Flatts Maren Morris and Niall Horan Brad Paisley and Kane Brown The all-star event also includes performances by Garth Brooks, Brothers Osborne,…