Starbucks stores across South Korea will close for half a day next week for staff to attend a history lesson following a promotional campaign gone awry, the coffee giant said on Monday.Starbucks Korea, with more than 2,000 stores nationwide, found itself embroiled in public uproar last month when it ran a “Tank Day” promotion evoking a deadly military crackdown on a 1980 pro-democracy uprising.The day of the reusable cup promotion – May 18 – coincided with the 46th anniversary of the Gwangju...