The brother of the Big Apple’s top cop called mayor-elect Zohran Mamdani an “enemy” of Jewish people during a fiery charity dinner speech where he railed about the future of the city. Benjamin Tisch — younger brother of police Commissioner Jessica Tisch — was presenting an award Wednesday evening during the Met Council’s annual holiday dinner when the top exec at the Loews Corporation skewered the radical DSA lawmaker, according to sources. Tisch, who is Jewish, worried about the direction of