Update validation.rst

Constraints works also on private and protected methods hose name starts with "get", "is" or "has".

Author: mohamedGasmii

validation.rst

@@ -519,7 +519,7 @@ of the form fields::
 Constraint Targets
 ------------------
 
-Constraints can be applied to a class property (e.g. ``name``), a public
+Constraints can be applied to a class property (e.g. ``name``), a
 getter method (e.g. ``getFullName()``) or an entire class. Property constraints
 are the most common and easy to use. Getter constraints allow you to specify
 more complex validation rules. Finally, class constraints are intended
@@ -635,7 +635,7 @@ Getters
 ~~~~~~~
 
 Constraints can also be applied to the return value of a method. Symfony
-allows you to add a constraint to any public method whose name starts with
+allows you to add a constraint to any private, protected or public method whose name starts with
 "get", "is" or "has". In this guide, these types of methods are referred to
 as "getters".