Lefty socialist and mayoral frontrunner Zohran Mamdani’s campaign quietly took in nearly $13,000 in potentially illegal foreign donations — including one from his mother-in-law in Dubai, The Post has learned. At least 170 of the nearly 54,000 contributions to the leading Democratic candidate’s campaign came from donors with addresses outside the United States, an examination of NYC Campaign Finance Board records found. Only US citizens or permanent legal residents are allowed to contribute to