CHICAGO — Jake Arrieta pitched six scoreless innings for his major league-leading 15th win, and Anthony Rizzo and Addison Russell homered to lead the Chicago Cubs to a 7-1 victory over the Atlanta Braves on Thursday night. Chicago snapped a three-game losing streak after winning nine straight and 15 of 16, with Arrieta (15-6) dominating on the mound and Rizzo and Russell supplying the power at the plate. Rizzo’s three-run drive capped a four-run third inning that saw Braves manager Fredi Gonzalez get ejected.