A federal judge Wednesday gave the green light to plaintiffs challenging the constitutionality of a Chicago ordinance that bars commercial advertisements inside or on the exterior of ridesharing vehicles.In a written opinion, U.S. District Judge Elaine Bucklo did not rule on the merits of the First Amendment and equal protection claims brought by ridesharing drivers and a company that offers interactive ads that can be displayed on tablets inside vehicles.But Bucklo held the city has not shown — at least in the early …