Amazon and more than a dozen of its subcontractors in New York City and the suburbs face union allegations they flouted a state law that protects employees from mass layoffs or closures. A complaint submitted to the state Labor Department on Tuesday by the International Brotherhood of Teamsters charges that Amazon and 13 subcontractors violated the state’s WARN Act by failing to give the megaretailer’s delivery drivers at least 90 days’ notice o…