Update bundle (with newest rubocop version) and fix offenses

app/models/concerns/creation.rb

@@ -7,8 +7,5 @@ module Creation
     belongs_to :user, polymorphic: true
     alias_method :author, :user
     alias_method :creator, :user
-
-    validates :user_id, presence: true
-    validates :user_type, presence: true
   end
 end