By Howard Schneider and Balazs Koranyi WASHINGTON (Reuters) – Global central banks hoping that high inflation would ease through improving global supply chains saw little relief through April as new coronavirus lockdowns in China and the war in Ukraine lengthened delivery times and drove costs higher, new analyses from the New York Federal Reserve and others indicates. A global supply chain pressure index, released on Wednesday by the New York Fed, rose in April after four months in which supply troubles appeared to ease, a reversal that, if continued, potentially means more persistent inflati…