style: correct coding style with rubocop linter

test/models/application_record_test.rb

@@ -11,4 +11,4 @@ class ApplicationRecordTest < ActiveSupport::TestCase
     assert_kind_of Class, ApplicationRecord
     assert ApplicationRecord < ActiveRecord::Base
   end
-end
+end

test/models/ticket_test.rb

@@ -254,4 +254,3 @@ class TicketTest < ActiveSupport::TestCase
     assert ticket.save
   end
 end
-

test/models/user_test.rb

@@ -63,4 +63,4 @@ class UserTest < ActiveSupport::TestCase
     refute user.valid?, "User with last_name longer than 12 chars should be invalid"
     assert_not_nil user.errors[:last_name], "No validation error for too long last_name"
   end
-end
+end