He lost his “dream” job! A Central Park maintenance worker who got canned for snoozing on the job insists his cat naps were caused by a legit sleep apnea disorder, according to a new lawsuit. Gregory Holder, 60, is suing the Central Park Conservancy for damages — alleging he was axed from a longtime position he loved last year due to “daytime drowsiness” from the recognized disability.  Gregory Holder is suing the Central Park Conservancy, alleging he was canned after eight years of work at a job he loved because of a disclosed disability. Stephen Yang for NY Post “[Holder] was stunned to be terminated after eight years of exemplary service and four promotions,” according to the lawsuit, filed Wednesday in Manhattan Supreme Court.…