WEST PALM BEACH, Fla. — Dusty Baker grins. “I’m spoiled,” the Astros skipper says. “Winning spoils you.” Being defending World Series champions isn’t enough. No team has repeated as champs since the Yankees won back-to-back-to-back titles from 1998 to 2000. Houston has its sights set on being the next. Winning three titles in seven years would be remarkable. But just ask a fan base — yes, Baker opines, they’re spoiled too — that had thousands lined up for hours at the team store in the middle of the night to buy exclusive gilded merchandise: this is the golden era of…