Ensure proper string management

config/public_statics_config.js

@@ -5,8 +5,8 @@
  * Note: don't modify its contents unless it's coordinated to work with deployments in different environments
  */
 
-const CARTO_BUILDER_ASSET_HOST = process.env.CARTO_BUILDER_ASSET_HOST || '//';
-const CARTO_MAPS_API_V2_EXTERNAL_URL = process.env.CARTO_MAPS_API_V2_EXTERNAL_URL || 'http://localhost.lan:8282';
+const CARTO_BUILDER_ASSET_HOST = JSON.stringify(process.env.CARTO_BUILDER_ASSET_HOST || '/assets');
+const CARTO_MAPS_API_V2_EXTERNAL_URL = JSON.stringify(process.env.CARTO_MAPS_API_V2_EXTERNAL_URL || 'http://localhost.lan:8282');
 
 module.exports = {
   'CARTO_BUILDER_ASSET_HOST': CARTO_BUILDER_ASSET_HOST,