Shein’s listing is a test of investor appetite for internet retailers, an industry that has struggled recently against the headwinds of inflation, trade disruptions and consumer caution in key markets including China. The stock code of online fashion retailer Shein is displayed on a screen during its listing ceremony at the Hong Kong Stock Exchange. (Courtesy: Reuters photo) Shein Global Holdings Ltd. shares opened flat in their Hong Kong debut after an initial public offering that raised HK$13.6 billion ($1.7 billion).The shares traded at the IPO price of HK$48.56, which priced the company just above the middle of its marketed…