Forbes has shut down reports that Kim Kardashian is now a billionaire after she sold 20 percent stake of her beauty line to American multinational beauty company, COTY, for $200 million. This comes after her husband, rapper Kanye West took to social media on Tuesday, June 30, to congratulate her on becoming a billionaire after her deal with COTY. According to Forbes, the 39-year-old reality star and mother of four is worth about $900million after inking a deal …