Oscar Isaac is letting go of his chic Brooklyn penthouse, putting his sprawling four-bedroom, three-bath duplex on the market for a cool $4.5 million, The Post has learned. The famed “Star Wars” and “Dune” actor snagged this trophy residence back in 2018 for $4.49 million, perched right in Brooklyn’s vibrant cross-section of Boerum Hill, Cobble...