Last week, Xiaomi posted a video of CyberOne, a humanoid bot that looks a lot like designs for Tesla's Optimus. Elon Musk has said a prototype of a Tesla bot could be unveiled as soon as September. Xiaomi's new bot could provide some insight into what to expect for Tesla's AI day. Xiaomi beat Tesla to building a functional humanoid robot, but the design for its CyberOne robot looks eerily similar to the electric-car maker's Optimus. Last week, the Chinese tech company unveiled its first look at CyberOne during a live event in Beijing. The humanoid bot was able to…