Ernie Johnson has seen many iconic moments in 34 years as host of “Inside the NBA.” However, nothing might top doing the postgame show Wednesday night from center court at Madison Square Garden after the New York Knicks made the greatest comeback in NBA Finals history to beat the San Antonio Spurs in Game 4. “That’s the best. None of the fans are leaving. They just want to soak this whole thing in. It was like a college atmosphere. And then to do the show right there with that energy going on,