DENVER — A suburban Denver baker who would not make a wedding cake for a same-sex couple cannot cite his Christian beliefs in refusing them service because it would lead to discrimination, the Colorado Court of Appeals ruled Thursday. The three-judge panel said in a 66-page ruling that Colorado’s anti-discrimination law does not prevent baker Jack Phillips from believing what he wants but that if he wants his business open to the public, he is prohibited “from picking and choosing customers based on their sexual orientation.” The decision is the latest victory for gay couples, who have won similar cases in other states.