Scarlett Johansson and Chris Hemsworth have been Avenging together for the better part of a decade, so you'd think the Avengers: Endgame co-stars would be pretty comfortable throwing some friendly barbs at each other. You'd be wrong, but that doesn't mean it's not a treat to watch them try. The duo stopped by BBC 1 Radio's ongoing series 'Playground Insults', which sees Hollywood superstars trade jabs at each other for the lols. If you missed previous installments, co-stars like Mark Wahlberg and Will Ferrell, Margot Robbie and Will Smith, and Jennifer Lawrence and …