[Chore] Add bullet gem #249 (#281)

* closes #249 add bullet gem

- upgrade gems
- fix the warning in the console
- fix the deprecation message for where not

spec/rails_helper.rb

@@ -4,7 +4,6 @@ require File.expand_path('../config/environment', __dir__)
 # Prevent database truncation if the environment is production
 abort('The Rails environment is running in production mode!') if Rails.env.production?
 require 'rspec/rails'
-require 'action_cable/testing/rspec'
 
 # Add additional requires below this line. Rails is not loaded until this point!