John Mulaney is an old-fashioned type of comedian. A showman, if you will. He wears a suit on stage, speaks in a transatlantic accent, and crafts his jokes with impeccable, Catskills-feeling tightness. And now, with a new variety special announced for Netflix, Mulaney is leaning in even harder to his retro sensibilities. John Mulaney & the Sack Lunch Bunch, featuring Mulaney and a bunch of cute, super-talented kids, comes to Netflix December 24, 2019 -- aka Christmas Eve. Remember "that bygone television era when children sang songs about their feelings with celebrity guests on funky outdoor sets"? Mulaney …