HONG KONG (REUTERS) – China's Tencent Holdings suffered its first ever quarterly sales fall on Wednesday, hurt by a government clampdown on game approvals and playing time, as well as Covid-19 lockdowns and a weakening economy that squeezed ad sales. The contraction marks a nadir for the gaming giant and owner of the WeChat messaging platform which has reported double digit growth almost every quarter since it went public in 2004, as Beijing's crackdown on big tech companies that began in late 2020 puts the brakes on its expansion. Tencent plans to sell all or a bulk of its US$24…