The NYPD is again expanding its footprint to deal with the migrant crisis and drug trafficking, posting one detective in Arizona and another in Colombia, a top department official said Wednesday. The new outposts — in Tuscon and Bogotá — bring to 18 the number of cities, mostly foreign, where the largest police department in the U.S. has assigned an investigator to work closely with authorities in each location. Deputy Commissioner Rebecca Weiner said the goal is for the NYPD to get accurate information as quickly as possible if an event elsewhere could impact the city, such as Oct. 7, when th…