minor #18791 [Validator] Missing information about payload in callback (alamirault)

This PR was merged into the 5.4 branch.

Discussion
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[Validator] Missing information about payload in callback

Fix #18787

Commits
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ab647bf Missing information about payload in callback

Author: javiereguiluz

reference/constraints/Callback.rst

@@ -304,11 +304,12 @@ callback method:
 * A closure.
 
 Concrete callbacks receive an :class:`Symfony\\Component\\Validator\\Context\\ExecutionContextInterface`
-instance as only argument.
+instance as the first argument and the :ref:`payload option <payload>` as the second argument.
 
 Static or closure callbacks receive the validated object as the first argument
-and the :class:`Symfony\\Component\\Validator\\Context\\ExecutionContextInterface`
-instance as the second argument.
+, the :class:`Symfony\\Component\\Validator\\Context\\ExecutionContextInterface`
+instance as the second argument and the :ref:`payload option <payload>` as the
+third argument.
 
 .. include:: /reference/constraints/_groups-option.rst.inc