TOKYO—Japan’s exports extended double-digit gains in August, led by strong shipments of chip manufacturing equipment, although the pace of growth weakened as COVID-19 hit key Asian supply chains and slowed factory production. The trade growth is unlikely to dispel worries about the outlook for Japan’s economy, which has not yet recovered to pre-pandemic levels after taking an enormous hit from a collapse in global trade in the first quarter of 2020. Exports rose 26.2 percent in August compared with the same month a year earlier, the Ministry of Finance said on Thursday, marking the sixth straight month of double-digit growth as strong demand for chip-making equipment offset slowing U.S and European Union-bound shipments of cars. However, the growth was slower than the 34.0 percent expected by economists in a Reuters poll and the 37.0 percent advance in the previous month. “Exports have been driving the economy. The recovery scenario for …