[WCM] [HttpFoundation] Added a switch to delete file after the response is send

| Q             | A
| ------------- | ---
| Doc fix?      | no
| New docs?     | https://github.com/symfony/symfony/pull/11212
| Applies to    | master
| Fixed tickets | N/A
you must add a `.. versionadded:: 2.6` directive before this paragraph:

````rst
.. versionadded:: 2.6
    The ``deleteFileAfterSend()`` method was introduced in Symfony 2.6.
````

(of course, you need to change 2.6 to whatever version your code PR is merged)