High-altitude climbers can soon look forward to birthday gifts, a warm pair of socks and even that frozen steak they’ve been dreaming of on Mount Everest with the successful completion of a drone delivery on the craggy territory. Chinese drone maker DJI released a video showing one of its flying machines in a first-ever drone drop off of three oxygen bottles, food and other supplies to climbers at Everest base Camp 1, Agence French Presse reported. DJI Technology said last week that it teamed up with a Nepalese drone service company, a video production company, and certified Nepalese mountain …