Starbucks Coffee Korea said Thursday that it would test run cashless operations at three of its branches next month, amid the growing use of credit cards and mobile payments. Starbucks Coffee Korea officials promote the test-run of cashless stores. (Starbucks Coffee Korea)Three branches including two in Seoul -- one near Samseong Station in Gangnam and one in Guro -- and one in Pangyo in Seongnam will go cashless f...