fix: add country code assignment in city creation

- Include assignment of country code when creating a city
- Ensure that all relevant geographical data is accounted for during
  the city creation process

This change addresses a missing assignment of the country code for new
city records, ensuring that instances are complete and accurate.

lib/tasks/sync_geo_data.rake

@@ -168,6 +168,7 @@ namespace :geo do
 
       city = City.find_or_create_by!(name: data["name"]) do |c|
         c.country_id = country.id,
+        c.country_code = country.code,
         c.latitude = data["latitude"],
         c.longitude = data["longitude"]
       end