Fix deprecated ActiveRecord errors interface

Author: Vidas P

app/validators/owned_by_validator.rb

@@ -1,6 +1,6 @@
 class OwnedByValidator < ActiveModel::EachValidator
   def validate_each(record, attribute, association)
     return if association.all? { |s| s[options[:with]] == record[options[:with]] }
-    record.errors[attribute] << 'must be owned by you'
+    record.errors.add(attribute, :wrong_owner, message: 'must be owned by you')
   end
 end