minor #10830 [Validator] Added missing examples in IdenticalTo constraint (xElysioN)

This PR was merged into the 3.4 branch.

Discussion
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[Validator] Added missing examples in IdenticalTo constraint

Hi,
This fix #10829 (Missing YAML, XML and PHP example in Basic Usage)

And add missing space for ``age`` in Basic Usage.

Link of changes : https://pr-10830-trovf4q-nq3xa5jtywvyc.eu.s5y.io/reference/constraints/IdenticalTo.html

Commits
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ad78e1b fix #10829: add missing examples in IdenticalTo constraint

Author: javiereguiluz

reference/constraints/IdenticalTo.rst

@@ -30,7 +30,7 @@ Basic Usage
 The following constraints ensure that:
 
 * ``firstName`` of ``Person`` class is equal to ``Mary`` *and* is a string
-* ``age`` is equal to``20`` *and* is of type integer
+* ``age`` is equal to ``20`` *and* is of type integer
 
 .. configuration-block::
 
@@ -61,6 +61,8 @@ The following constraints ensure that:
         # src/AppBundle/Resources/config/validation.yml
         AppBundle\Entity\Person:
             properties:
+                firstName:
+                    - IdenticalTo: Mary
                 age:
                     - IdenticalTo:
                         value: 20
@@ -74,6 +76,11 @@ The following constraints ensure that:
             xsi:schemaLocation="http://symfony.com/schema/dic/constraint-mapping http://symfony.com/schema/dic/constraint-mapping/constraint-mapping-1.0.xsd">
 
             <class name="AppBundle\Entity\Person">
+                <property name="firstName">
+                    <constraint name="IdenticalTo">
+                        <value>Mary</value>
+                    </constraint>
+                </property>
                 <property name="age">
                     <constraint name="IdenticalTo">
                         <option name="value">20</option>
@@ -94,6 +101,8 @@ The following constraints ensure that:
         {
             public static function loadValidatorMetadata(ClassMetadata $metadata)
             {
+                $metadata->addPropertyConstraint('firstName', new Assert\IdenticalTo('Mary'));
+
                 $metadata->addPropertyConstraint('age', new Assert\IdenticalTo(array(
                     'value' => 20,
                 )));