minor #9600 [PropertyInfo] Complete the list of built-in types supported (fmata)

This PR was merged into the 2.8 branch.

Discussion
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[PropertyInfo] Complete the list of built-in types supported

symfony/symfony#24571 introduced `iterable` type but the doc has not been updated.

Commits
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8097eb9 Update property_info.rst

Author: javiereguiluz

components/property_info.rst

@@ -285,7 +285,7 @@ Type::getBuiltInType()
 The :method:`Type::getBuiltinType() <Symfony\\Component\\PropertyInfo\\Type::getBuiltinType>`
 method will return the built-in PHP data type, which can be one of 9 possible
 string values: ``array``, ``bool``, ``callable``, ``float``, ``int``, ``null``,
-``object``, ``resource`` or ``string``.
+``object``, ``resource``, ``string`` or ``iterable``.
 
 Constants inside the :class:`Symfony\\Component\\PropertyInfo\\Type`
 class, in the form ``Type::BUILTIN_TYPE_*``, are provided for convenience.