Fix warning in Ch08 - Validate quantity of products (#60)

Author: notapatch

rails6/en/chapter08-improve-orders.adoc

@@ -383,7 +383,7 @@ class EnoughProductsValidator < ActiveModel::Validator
     record.placements.each do |placement|
       product = placement.product
       if placement.quantity > product.quantity
-        record.errors[product.title.to_s] << "Is out of stock, just #{product.quantity} left"
+        record.errors.add product.title,  "Is out of stock, just #{product.quantity} left"
       end
     end
   end

rails6/es/chapter08-improve-orders.adoc

@@ -382,7 +382,7 @@ class EnoughProductsValidator < ActiveModel::Validator
     record.placements.each do |placement|
       product = placement.product
       if placement.quantity > product.quantity
-        record.errors[product.title.to_s] << "Is out of stock, just #{product.quantity} left"
+        record.errors.add product.title,  "Is out of stock, just #{product.quantity} left"
       end
     end
   end

rails6/fr/chapter08-improve-orders.adoc

@@ -378,7 +378,7 @@ class EnoughProductsValidator < ActiveModel::Validator
     record.placements.each do |placement|
       product = placement.product
       if placement.quantity > product.quantity
-        record.errors[product.title.to_s] << "Is out of stock, just #{product.quantity} left"
+        record.errors.add product.title,  "Is out of stock, just #{product.quantity} left"
       end
     end
   end