DETROIT — U.S. Transportation Secretary Pete Buttigieg and his husband Chasten are officially Michiganians — a move that may help bolster the former South Bend, Indiana mayor’s future political prospects. The couple have moved to Traverse City, Chasten’s hometown, and plan to register to vote there before the midterm election this fall, a U.S. Department of Transportation spokesperson confirmed to The Detroit News. The move will allow the Buttigiegs to be closer to Chasten’s parents, who have helped the couple with child care since they adopted their twins last August, according to the spokesp…