The Vatican on Thursday unexpectedly ended its controversial reform of the main umbrella group of U.S. nuns, cementing a shift in tone and treatment of the U.S. sisters under the social justice-minded Pope Francis. The Vatican said it had accepted a final report on its overhaul of the Leadership Conference of Women Religious and declared that the “implementation of the mandate has been accomplished” nearly two years ahead of schedule. It was an abrupt about-face given that just last year, the head of the Vatican’s doctrine office, Cardinal Gerhard Mueller, sharply rebuked the LCWR for its “regrettable” attitude and behavior...