A top deputy to city schools Chancellor Richard Carranza was busted in Wisconsin for allegedly trying to arrange sex with an underage boy online, police and sources told The Post. Department of Education deputy chief of staff David Hay was arrested at General Mitchell International Airport in Milwaukee on Sunday on a charge of using a computer “to facilitate a child sex crime,” according to cops in Neenah, Wisconsin. He allegedly intended to meet with a minor boy for sex, sources said. Hay, who remained behind bars pending a bail hearing Monday, had been under investigation for several months, sources...