Arnold Schwarzenegger’s son Joseph Baena, who looks and sounds just like the actor and former governor of California, is a realtor now and he’s showing off multimillion-dollar mansions as he works towards becoming an action movie star just like his father. In an exclusive interview with Inside Edition that aired Thursday, the 24-year-old son of Schwarzenegger revealed his side hustle. He’s a real estate agent in Beverly Hills who, although he has a famous last name, chooses not to use it. “I like my last name,” Baena told the outlet. “Why change it.” Unlike Schwarzenegger’s other children, Bae…