Fix ActionController::UrlGenerationError for controller tests in Rails engines

controller_helpers.rb

# spec/support/helpers/controller_helpers.rb
module ControllerHelpers
  extend ActiveSupport::Concern

  included do
    routes { ProfileApi::Engine.routes }
  end
end

rails_helper.rb

# spec/rails_helper.rb
Dir[File.expand_path('../support/**/*.rb', __FILE__)].each { |f| require f }

RSpec.configure do |config|
  config.include ControllerHelpers, type: :controller
end