style(rubocop): fix all safe auto correctable offenses

Rakefile

@@ -1,6 +1,6 @@
 # Add your own tasks in files placed in lib/tasks ending in .rake,
 # for example lib/tasks/capistrano.rake, and they will automatically be available to Rake.
 
-require_relative 'config/application'
+require_relative "config/application"
 
 Rails.application.load_tasks