Dozens of U.S. diplomats and their families are leaving Saudi Arabia this weekend amid a surge in new coronavirus cases, drawing into focus the kingdom’s struggle in containing the outbreak as it reopens its economy. The diplomats will take a repatriation flight Saturday after the State Department last week approved the voluntary departure of non-emergency personnel, U.S. officials familiar with the plan said. More diplomats are expected to follow in the coming weeks, they added. …