By Bonnie Stiernberg Back in June, Lizzo apologized and changed the lyrics of her song “GRRRLS” to remove the word “spaz” after disability advocates on social media pointed out that the term is an ableist slur. It was a rare instance of a celebrity listening to criticism and acting accordingly instead of getting defensive, and it served as a teaching moment for many people who were perhaps unaware that the word is offensive. Those people, apparently, do not include Beyoncé. The “Drunk in Love” singer finds herself in hot water over “Heated,” a track on her new album Renaissance that uses the s…