Update the generate command sample codes [skip ci]

[soartec-lab]

Summary

Since the files generated by generate command scaffold have changed, the sample code has been updated.

Other Information

$ bin/rails generate scaffold HighScore game:string score:integer
invoke  active_record
create    db/migrate/20190416145729_create_high_scores.rb
create    app/models/high_score.rb
invoke    test_unit
create      test/models/high_score_test.rb
create      test/fixtures/high_scores.yml
invoke  resource_route
 route    resources :high_scores
invoke  scaffold_controller
create    app/controllers/high_scores_controller.rb
invoke    erb
create      app/views/high_scores
create      app/views/high_scores/index.html.erb
create      app/views/high_scores/edit.html.erb
create      app/views/high_scores/show.html.erb
create      app/views/high_scores/new.html.erb
create      app/views/high_scores/_form.html.erb
invoke    test_unit
create      test/controllers/high_scores_controller_test.rb
create      test/system/high_scores_test.rb
invoke    helper
create      app/helpers/high_scores_helper.rb
invoke      test_unit
invoke    jbuilder
create      app/views/high_scores/index.json.jbuilder
create      app/views/high_scores/show.json.jbuilder
create      app/views/high_scores/_high_score.json.jbuilder
invoke  assets
invoke    scss
create      app/assets/stylesheets/high_scores.scss
invoke  scss
create    app/assets/stylesheets/scaffolds.scss

$ bin/rails -v
Rails 6.0.0.beta3

[soartec-lab]

Thank you merge !