BEIJING—Growth in China’s June factory activity dipped to a four-month low on higher raw material costs, a shortage of semiconductors, and a COVID-19 outbreak in the major export province of Guangdong, amid wider supply chain disruptions in Asia. The chip supply crunch has hammered other manufacturing powerhouses in Asia. Industrial output in Japan and South Korea slumped in May from the previous month as auto production declined due to semiconductor shortages, adding to concerns of flagging momentum in their respective economies. China’s June official manufacturing Purchasing Manager’s Index (PMI) eased slightly to 50.9 versus 51.0 in May, data from the National Bureau of Statistics showed on Wednesday. It, however, exceeded analysts’ forecast for a slowdown to 50.8. It remained above the 50-point mark that separates growth from contraction on a monthly basis. The soft factory activity data aided a rebound in Chinese stocks on Wednesday as it eased fears of …