Chinese self-driving firm Beijing Momenta Technology Co. has filed confidentially for an initial public offering in the US, according to people familiar with the matter.Momenta is working with China International Capital Corp., Goldman Sachs Group Inc. and UBS Group AG on a potential listing that may happen as early as this year, the people said, asking not to be identified discussing a private matter. It could raise $200 million to $300 million from the share sale, the people said....