Chilling video captures the moment a Los-Angeles-based drill rapper was shot dead inside a Bronx pharmacy in broad daylight by a group of four men trying to steal his gold chain. The disturbing footage — obtained by The Post Friday — shows the crew mercilessly attacking Avanti Frowner, 27, inside Amazing Pharmacy on East Tremont Avenue near Arthur Avenue around 3:45 p.m. Thursday before one of the men shot and killed him. “They don’t need to be on the streets no more – ever!” Avanti’s dad, Roger Frowner, 56, told The Post. “If they kill somebody in broad daylight, inside...