minor #15208 [Ldap] Update ldap.rst (jraller)

This PR was submitted for the 5.2 branch but it was squashed and merged into the 4.4 branch instead.

Discussion
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[Ldap] Update ldap.rst

include documentation of the filter option for the query command.

Commits
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2e77005 [Ldap] Update ldap.rst

Author: javiereguiluz

components/ldap.rst

@@ -115,6 +115,11 @@ to the ``LDAP_SCOPE_BASE`` scope of :phpfunction:`ldap_read`) and ``SCOPE_ONE``
 
     $query = $ldap->query('dc=symfony,dc=com', '...', ['scope' => QueryInterface::SCOPE_ONE]);
 
+To retrieve only specific attributes you can specify which attributes you want returned using 
+the ``filter`` option::
+
+    $query = $ldap->query('dc=symfony,dc=com', '...', ['filter' => ['cn, mail']);
+
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