Replace left over "annotation" by "attribute"

Author: sascha-egerer

components/validator/resources.rst

@@ -102,7 +102,7 @@ the metadata from the attributes of the class. For example::
 To enable the attribute loader, call the
 :method:`Symfony\\Component\\Validator\\ValidatorBuilder::enableAttributeMapping` method.
 
-To disable the annotation loader after it was enabled, call
+To disable the attribute loader after it was enabled, call
 :method:`Symfony\\Component\\Validator\\ValidatorBuilder::disableAttributeMapping`.
 
 Using Multiple Loaders