Add email validation errors via add (#1445)

Author: artplan1

app/validators/devise_token_auth_email_validator.rb

@@ -3,7 +3,7 @@
 class DeviseTokenAuthEmailValidator < ActiveModel::EachValidator
   def validate_each(record, attribute, value)
     unless value =~ /\A([^@\s]+)@((?:[-a-z0-9]+\.)+[a-z]{2,})\z/i
-      record.errors[attribute] << email_invalid_message
+      record.errors.add(attribute, email_invalid_message)
     end
   end