Dave McNary Film ReporterAnne Hathaway and Bill Murray are starring in the canine drama “Bum’s Rush,” with Robert Duvall in talks to come on board.Rocket Science announced the castings on Tuesday at the virtual Cannes Market. CAA Media Finance represents the domestic rights, with Rocket Science handling international sales.Aaron Schneider, who directed the upcoming Tom Hanks war drama “Greyhound,” is helming “Bum’s Rush” from C.