Open this photo in gallery: The U.S. head office of TikTok is shown in Culver City, California on Sept. 15, 2020.Mike Blake/Reuters Billionaire Elon Musk said that he was not interested in purchasing TikTok, the popular short-video app that the United States has been trying to ban over national security concerns with its Chinese owner ByteDance. Musk’s comments, made in late January, were released online Saturday by The WELT Group, a part of the German media company Axel Springer SE, which hosted a summit, where the Tesla chief joined the conference via video. “I have not put in a bid…