Courtesy DDOT A long-awaited traffic pattern change at the intersection of New York and Florida avenues NE is set to begin at 9 p.m. on June 4, the District Dept. of Transportation announced Tuesday. Once the changes are put into place, southbound First Street will become one-way between Florida and New York, westbound Florida will become one-way between New York and First, and eastbound Florida will be detoured to First. Traffic will be able…