JONATHAN ALLEN A Minneapolis homicide investigator said police officer Derek Chauvin used "totally unnecessary" deadly force when kneeling on George Floyd's neck during an arrest last May in testimony at Chauvin's murder trial yesterday. Chauvin, who is white, was fired by the city's police department the day after he was captured on video on top of a dying Floyd, a 46-year-old Black man in handcuffs, in a scene that sparked protests against police brutality around the world. "Totally unnecessary," Lieutenant Richard Zimmerman told the jury when prosecutors asked him what he thought of Chauvin pressing his knee on Floyd's neck…