Include RailsExampleGroup in spec

Now that we've confirmed the failing test, by including RailsExampleGroup, it should reset CurrentAttributes as expected.

Author: javierjulio

spec/rspec/rails/example/rails_example_group_spec.rb

@@ -34,6 +34,8 @@ module RSpec::Rails
     end
 
     describe 'CurrentAttributes', order: :defined do
+      include RSpec::Rails::RailsExampleGroup
+
       class Current < ActiveSupport::CurrentAttributes
         attribute :request_id
       end