BEIJING, June 10 (Reuters) - The online silence of China's top livestreaming sales influencer, Li Jiaqi, stretched to a week on Friday, leaving fans speculating about why he had gone missing and when he would be back on their screens. Also known by his English name Austin, Li has more than 64 million followers for his livestreaming channel on Alibaba Group Taobao Marketplace where he sells a wide range of...