A Jersey City police officer forged half a dozen documents so he could take an extra eight weeks of medical leave, Hudson County Prosecutor Esther Suarez said Tuesday. The officer, 31-year-old Justin Rivera, was arrested Tuesday by members of the Hudson County Prosecutor’s Office Internal Affairs Unit and charged with six counts of forgery/uttering forged documents, a fourth-degree offense. Rivera, who joined the police department in January 2019, was released pending his first court appearance, which is tentatively scheduled for July 9. Suarez says that between March 2022 and January 2023, Ri…