“Mulan” star Tzi Ma is frequently recognized for his many film and television roles, including in last year’s indie hit “The Farewell” and the “Rush Hour” films. But it was an encounter weeks ago that has stayed with him. Ma had visited a Whole Foods grocery store in Pasadena, Calif., when a car approached him as he made his way to the entrance. “He rolls down the window and goes, ‘You should be quarantined,’ and then he took off,” Ma told Variety. He said he stood, speechless, before unleashing screams at the verbal assaulter, who was by then long gone....