Knicks owner James Dolan’s joke about giving up sex during the NBA playoffs has been revealed. “I had this idea that maybe you should give up sex for the next 10 weeks,” Dolan told the Knicks before the playoffs on Apr. 3. “You don’t have to give up sex for the next 10 weeks, but like Spartans — do you know what Spartans are? — they denied themselves to gain an edge. Get the edge.” The joke was part of a 15-minute surprise speech Dolan gave to the Knicks about making sacrifices to end the