Marc Malkin Senior Film Awards, Events & Lifestyle EditorMandy Moore insists she doesn’t know the complete history of Rebecca Pearson and Miguel Rivas’ relationship on “This Is Us.”“I know as much as the audience knows at this point — Rebecca and Miguel were in each other’s lives,” Moore, who earned an Emmy nomination last year for her work as Rebecca, says on Tuesday’s episode of the Variety and iHeart podcast “The Big Ticket.”“I think she particularly leaned on him a little heavier,” she