I'm getting this error using Ubuntu + Apache + Passenger.
The problem is that I'm not using any database or model.

```
undefined method `has_one_attached' for #<Class:0x0000555c6ad94fd8> (NoMethodError)
  /usr/local/rvm/gems/ruby-2.5.1/gems/activerecord-5.2.1/lib/active_record/dynamic_matchers.rb:22:in `method_missing'
  /usr/local/rvm/gems/ruby-2.5.1/gems/activestorage-5.2.1/app/models/active_storage/blob/representable.rb:7:in `block in <module:Representable>'
  /usr/local/rvm/gems/ruby-2.5.1/gems/activesupport-5.2.1/lib/active_support/concern.rb:122:in `class_eval'
  /usr/local/rvm/gems/ruby-2.5.1/gems/activesupport-5.2.1/lib/active_support/concern.rb:122:in `append_features'
  /usr/local/rvm/gems/ruby-2.5.1/gems/activestorage-5.2.1/app/models/active_storage/blob.rb:23:in `include'
  /usr/local/rvm/gems/ruby-2.5.1/gems/activestorage-5.2.1/app/models/active_storage/blob.rb:23:in `<class:Blob>'
  /usr/local/rvm/gems/ruby-2.5.1/gems/activestorage-5.2.1/app/models/active_storage/blob.rb:16:in `<main>'
  /usr/local/rvm/gems/ruby-2.5.1/gems/bootsnap-1.4.1/lib/bootsnap/load_path_cache/core_ext/kernel_require.rb:21:in `require'
  /usr/local/rvm/gems/ruby-2.5.1/gems/bootsnap-1.4.1/lib/bootsnap/load_path_cache/core_ext/kernel_require.rb:21:in `block in require_with_bootsnap_lfi'
  /usr/local/rvm/gems/ruby-2.5.1/gems/bootsnap-1.4.1/lib/bootsnap/load_path_cache/loaded_features_index.rb:83:in `register'
  /usr/local/rvm/gems/ruby-2.5.1/gems/bootsnap-1.4.1/lib/bootsnap/load_path_cache/core_ext/kernel_require.rb:20:in `require_with_bootsnap_lfi'
  /usr/local/rvm/gems/ruby-2.5.1/gems/bootsnap-1.4.1/lib/bootsnap/load_path_cache/core_ext/kernel_require.rb:29:in `require'
  /usr/local/rvm/gems/ruby-2.5.1/gems/activesupport-5.2.1/lib/active_support/dependencies.rb:287:in `block in require'
  /usr/local/rvm/gems/ruby-2.5.1/gems/activesupport-5.2.1/lib/active_support/dependencies.rb:253:in `load_dependency'
  /usr/local/rvm/gems/ruby-2.5.1/gems/activesupport-5.2.1/lib/active_support/dependencies.rb:287:in `require'
  /usr/local/rvm/gems/ruby-2.5.1/gems/activesupport-5.2.1/lib/active_support/dependencies.rb:374:in `block in require_or_load'
  /usr/local/rvm/gems/ruby-2.5.1/gems/activesupport-5.2.1/lib/active_support/dependencies.rb:37:in `block in load_interlock'
  /usr/local/rvm/gems/ruby-2.5.1/gems/activesupport-5.2.1/lib/active_support/dependencies/interlock.rb:14:in `block in loading'
  /usr/local/rvm/gems/ruby-2.5.1/gems/activesupport-5.2.1/lib/active_support/concurrency/share_lock.rb:151:in `exclusive'
  /usr/local/rvm/gems/ruby-2.5.1/gems/activesupport-5.2.1/lib/active_support/dependencies/interlock.rb:13:in `loading'
  /usr/local/rvm/gems/ruby-2.5.1/gems/activesupport-5.2.1/lib/active_support/dependencies.rb:37:in `load_interlock'
  /usr/local/rvm/gems/ruby-2.5.1/gems/activesupport-5.2.1/lib/active_support/dependencies.rb:352:in `require_or_load'
  /usr/local/rvm/gems/ruby-2.5.1/gems/bootsnap-1.4.1/lib/bootsnap/load_path_cache/core_ext/active_support.rb:48:in `block in require_or_load'
  /usr/local/rvm/gems/ruby-2.5.1/gems/bootsnap-1.4.1/lib/bootsnap/load_path_cache/core_ext/active_support.rb:16:in `allow_bootsnap_retry'
  /usr/local/rvm/gems/ruby-2.5.1/gems/bootsnap-1.4.1/lib/bootsnap/load_path_cache/core_ext/active_support.rb:47:in `require_or_load'
  /usr/local/rvm/gems/ruby-2.5.1/gems/activesupport-5.2.1/lib/active_support/dependencies.rb:330:in `depend_on'
  /usr/local/rvm/gems/ruby-2.5.1/gems/bootsnap-1.4.1/lib/bootsnap/load_path_cache/core_ext/active_support.rb:82:in `depend_on'
  /usr/local/rvm/gems/ruby-2.5.1/gems/activesupport-5.2.1/lib/active_support/dependencies.rb:244:in `require_dependency'
  /usr/local/rvm/gems/ruby-2.5.1/gems/railties-5.2.1/lib/rails/engine.rb:478:in `block (2 levels) in eager_load!'
  /usr/local/rvm/gems/ruby-2.5.1/gems/railties-5.2.1/lib/rails/engine.rb:477:in `each'
  /usr/local/rvm/gems/ruby-2.5.1/gems/railties-5.2.1/lib/rails/engine.rb:477:in `block in eager_load!'
  /usr/local/rvm/gems/ruby-2.5.1/gems/railties-5.2.1/lib/rails/engine.rb:475:in `each'
  /usr/local/rvm/gems/ruby-2.5.1/gems/railties-5.2.1/lib/rails/engine.rb:475:in `eager_load!'
  /usr/local/rvm/gems/ruby-2.5.1/gems/railties-5.2.1/lib/rails/engine.rb:356:in `eager_load!'
  /usr/local/rvm/gems/ruby-2.5.1/gems/railties-5.2.1/lib/rails/application/finisher.rb:69:in `each'
  /usr/local/rvm/gems/ruby-2.5.1/gems/railties-5.2.1/lib/rails/application/finisher.rb:69:in `block in <module:Finisher>'
  /usr/local/rvm/gems/ruby-2.5.1/gems/railties-5.2.1/lib/rails/initializable.rb:32:in `instance_exec'
  /usr/local/rvm/gems/ruby-2.5.1/gems/railties-5.2.1/lib/rails/initializable.rb:32:in `run'
  /usr/local/rvm/gems/ruby-2.5.1/gems/railties-5.2.1/lib/rails/initializable.rb:61:in `block in run_initializers'
  /usr/local/rvm/rubies/ruby-2.5.1/lib/ruby/2.5.0/tsort.rb:228:in `block in tsort_each'
  /usr/local/rvm/rubies/ruby-2.5.1/lib/ruby/2.5.0/tsort.rb:350:in `block (2 levels) in each_strongly_connected_component'
  /usr/local/rvm/rubies/ruby-2.5.1/lib/ruby/2.5.0/tsort.rb:431:in `each_strongly_connected_component_from'
  /usr/local/rvm/rubies/ruby-2.5.1/lib/ruby/2.5.0/tsort.rb:349:in `block in each_strongly_connected_component'
  /usr/local/rvm/rubies/ruby-2.5.1/lib/ruby/2.5.0/tsort.rb:347:in `each'
  /usr/local/rvm/rubies/ruby-2.5.1/lib/ruby/2.5.0/tsort.rb:347:in `call'
  /usr/local/rvm/rubies/ruby-2.5.1/lib/ruby/2.5.0/tsort.rb:347:in `each_strongly_connected_component'
  /usr/local/rvm/rubies/ruby-2.5.1/lib/ruby/2.5.0/tsort.rb:226:in `tsort_each'
  /usr/local/rvm/rubies/ruby-2.5.1/lib/ruby/2.5.0/tsort.rb:205:in `tsort_each'
  /usr/local/rvm/gems/ruby-2.5.1/gems/railties-5.2.1/lib/rails/initializable.rb:60:in `run_initializers'
  /usr/local/rvm/gems/ruby-2.5.1/gems/railties-5.2.1/lib/rails/application.rb:361:in `initialize!'
  /var/www/app/config/environment.rb:5:in `<top (required)>'
  config.ru:3:in `require_relative'
  config.ru:3:in `block in <main>'
  /usr/local/rvm/gems/ruby-2.5.1/gems/rack-2.0.6/lib/rack/builder.rb:55:in `instance_eval'
  /usr/local/rvm/gems/ruby-2.5.1/gems/rack-2.0.6/lib/rack/builder.rb:55:in `initialize'
  config.ru:1:in `new'
  config.ru:1:in `<main>'
  /usr/share/passenger/helper-scripts/rack-preloader.rb:101:in `eval'
  /usr/share/passenger/helper-scripts/rack-preloader.rb:101:in `preload_app'
  /usr/share/passenger/helper-scripts/rack-preloader.rb:189:in `block in <module:App>'
  /usr/lib/ruby/vendor_ruby/phusion_passenger/loader_shared_helpers.rb:380:in `run_block_and_record_step_progress'
  /usr/share/passenger/helper-scripts/rack-preloader.rb:188:in `<module:App>'
  /usr/share/passenger/helper-scripts/rack-preloader.rb:30:in `<module:PhusionPassenger>'
  /usr/share/passenger/helper-scripts/rack-preloader.rb:29:in `<main>'

```