After months of speculation about his future, former Bank of Canada governor Mark Carney launched his campaign to replace Justin Trudeau as Liberal leader on Thursday with a promise to build the fastest-growing economy in the G7 if he’s elected.Carney, 59, kicked off his campaign to take the reins of the governing party at the Edmonton-area hockey rink where he learned to skate as a boy while growing up on the Prairies.”I’m doing this because Canada is the best country in the world, but it still could be even better,” Carney said.The Harvard-educated Carney said he has the economic bona fides needed…