Mega chart-topper Beyoncé delivered a simple message to Americans while rallying supporters of Kamala Harris at a packed Houston stadium on Friday: “We need you.” “For all the men and women in this room and watching around the country: We need you,” the Houston native said during her short remarks that immediately followed a speech by her one-time Destiny’s Child bandmate Kelly Rowland. The group’s popular 1999 hit “Independent Woman, Part 1” welcomed the pair as they took the stage. “We must vote, and we need you,” Beyoncé continued. “It’s time for America to sing a new song. Our voices sing …