Stellar stand-up and former SNL writer John Mulaney bounced back from his failed Fox sitcom like a true boss, recording a widely beloved special aptly named The Comeback Kid. Now after a surprise stint as a Broadway darling with his and Nick Kroll’s two-man show, Oh, Hello, the kid is back on the road with a nearly-sold out tour — lucky for you, a second late show was added to Wednesday’s calendar at Davies Symphony Hall.