A 36-year-old convicted robber pleaded guilty Wednesday and was immediately sentenced to time served in jail for grabbing a girl at a Yorba Linda park. Marvin Alexander Rivera-Benitez pleaded guilty to a felony count of kidnapping a child younger than 14 for grabbing the arm of one girl, who kicked him and ran away as passersby and parents detained him until sheriff’s deputies arrived at Veterans Park, according to Orange County Sheriff’s Depart…