The resignation of four economic ministers in Thailand on Thursday has left investors anxious about how Southeast Asia’s worst-performing economy will recover from the impact of the Covid-19 pandemic, and the future of Chinese and Japanese investments in the country. Deputy prime minister Somkid Jatusripitak, known as the economic policy tsar, and finance minister Uttama Savanayana had overseen the roll-out of stimulus measures worth billions of dollars to boost the tourism-dependent economy,…