Britain’s ruling Conservatives lost two more parliamentary seats to Labour in by-elections Friday, highlighting the mountain Prime Minister Rishi Sunak must climb to win a general election due this year. The losses capped a dire week for the UK leader, struggling to revive support for his beleaguered party, as official data showed Britain is in recession after economic contraction for two successive quarters. In power since 2010, the Conservatives are widely tipped by pollsters to lose the nationwide vote that 43-year-old Sunak has said will be held in the second half of the year. The main Lab…