Fix poll expiration notify worker spec sometimes return error

spec/spec_helper.rb

@@ -1,5 +1,7 @@
 # frozen_string_literal: true
 
+require 'rspec/retry'
+
 if ENV['DISABLE_SIMPLECOV'] != 'true'
   require 'simplecov'
   SimpleCov.start 'rails' do
@@ -36,6 +38,10 @@ RSpec.configure do |config|
   config.after :suite do
     FileUtils.rm_rf(Dir[Rails.root.join('spec', 'test_files')])
   end
+
+  # for RSpec::Retry
+  config.verbose_retry = true
+  config.display_try_failure_messages = true
 end
 
 def body_as_json