Matt Damon was at the 2016 New York Comic Con at Madison Square Garden on Saturday promoting his upcoming film, “The Great Wall.’’ It was also his 46th birthday, and People magazine reported that the actor read aloud a humorous birthday text message that he received from his father, Kent. “My birthday present to you is that in exactly one month, we can kiss Trump goodbye,’’ Damon said, reading his dad’s text. “If he did get elected, Mexico would have to put up that wall to keep him out!’’