Fix remaining offense for Style/ExpandPathArguments

.rubocop_todo.yml

@@ -471,13 +471,6 @@ Style/EmptyElse:
 Style/EmptyMethod:
   Enabled: false
 
-# Offense count: 2
-# Cop supports --auto-correct.
-Style/ExpandPathArguments:
-  Exclude:
-    - 'cable/config.ru'
-    - 'config.ru'
-
 # Offense count: 118
 # Cop supports --auto-correct.
 Style/ExplicitBlockArgument:

config.ru

@@ -2,7 +2,7 @@
 
 # This file is used by Rack-based servers to start the application.
 
-require ::File.expand_path('../config/environment', __FILE__)
+require ::File.expand_path('config/environment', __dir__)
 
 warmup do |app|
   client = Rack::MockRequest.new(app)