Concord Casino mogul Andy Sanborn’s deal with federal prosecutors would send him to prison for one year and one day in exchange for his guilty plea to stealing more than a quarter-million dollars in COVID-19 relief money. Sanborn has not pleaded guilty yet, but he is due in U.S. District Court in Concord on July 7 for his official plea hearing. The plea agreement on file calls for prosecutors to recommend that Sanborn serve one year and one day …