isRouteExternal(routeId) {
    const routeConfig = this.getRouteConfigById(routeId);
    return !!(routeConfig && routeConfig.type === "url");
  }
Return true if the given route is external, false otherwise
Used to correctly (re)apply script tags when cloning the template to the DOM (createRouteContent)
@param {string} routeId Route ID to check
@returns {boolean} True if the given route is external, false otherwise