By Walt Hickey Formula 1 Formula 1 is heading to Vegas, and organizers are a little skittish because demand has been soft and they’re worried that the sport may be losing steam or may have grown too quickly in the United States. The sport, in which a number of racers drive highly sophisticated vehicles behind a Dutchman named Max Verstappen to figure out who gets to lose the least to him, had been growing sharply in the U.S. as it moved beyond its traditional base of Europe. The cheapest tickets for Friday’s race are selling for $259, about