The head of a notorious armed gang linked to the kidnapping of U.S. citizens in Haiti, including 16 missionaries, decided to plead guilty to federal weapons smuggling charges Tuesday while in the middle of his federal trial in Washington, D.C. Lawyers for Germine Joly, known as Yonyon, informed U.S. District Judge John D. Bates late Tuesday of Joly’s change of plea just as prosecutors were preparing to rest their case after eight days of testimony. Their last witness: a federal agent who testified that while on the May 2022 extradition flight from Port-au-Prince to Washington, the head of Hait…