Fixed ApplicationHelper dependency

app/models/carto/visualization_export.rb

@@ -36,14 +36,12 @@ module Carto
   end
 
   class DataExporter
-    include ApplicationHelper
-
     # Returns the file
     def export_table(user_table, folder, format)
       table_name = user_table.name
 
       query = %{select * from "#{table_name}"}
-      url = sql_api_query_url(query, table_name, user_table.user, privacy(user_table), format)
+      url = ::ApplicationHelper.sql_api_query_url(query, table_name, user_table.user, privacy(user_table), format)
       exported_file = "#{folder}/#{table_name}.#{format}"
       Carto::Http::Client.get('data_exporter', log_requests: true).get_file(url, exported_file)
     end

services/sql-api/sql_api.rb

@@ -5,7 +5,6 @@ require_relative '../../lib/carto/http/client'
 
 module CartoDB
   class SQLApi
-    include ApplicationHelper
 
     class SQLApiError < StandardError; end
     class SQLError < SQLApiError; end
@@ -23,7 +22,7 @@ module CartoDB
     # privacy: 'public' / 'private'
     def self.with_user(user, privacy)
       new(
-        base_url: ApplicationHelper.sql_api_url(user.username, privacy),
+        base_url: ::ApplicationHelper.sql_api_url(user.username, privacy),
         protocol: 'https',
         username: user.username,
         api_key: user.api_key