Stocks in Macau’s gaming operators jumped on Tuesday on news of a relaxation in border measures on arrivals from Guangdong province, the city’s key feeder market. The measure, announced Monday and coming into effect on Wednesday, relaxes the period of issuance for nucleic acid test results travellers must display to 7 days, from 48 hours. The announcement caused a 12.24 percent uptick in SJM Holding’s listed price on the Hong Kong Stock Exchange on Tuesday, the largest daily gain amongst the Big Six operators. The group opened its flagship property on the Cotai Strip on July 30th, a soft-debut that…