A company that supplies flowers to Home Depot stores is not liable for the actions of a supervisor who strangled a pregnant employee and then raped her corpse, a federal judge has held.In a written opinion on Tuesday, U.S. District Judge Jorge L. Alonso threw out a lawsuit accusing Grand Service LLC of negligence for allowing an “emotionally unstable and violent” man to remain on the job despite complaints he was abusing the employee he ultimately murdered.Brian Cooper’s slaying of Alisha Bromfield was …