Update access_denied_handler.rst

[talha-core]

getFlashBag() funciton is not there anymore

[xabbuh]

The method is still defined here: https://github.com/symfony/symfony/blob/6.3/src/Symfony/Component/HttpFoundation/Session/Session.php#L230

[talha-core]

The method is still defined here: https://github.com/symfony/symfony/blob/6.3/src/Symfony/Component/HttpFoundation/Session/Session.php#L230

I see, but phpstan throws error

[wouterj]

This is expected to error. If you want to be strict, you have to check if getSession() returns an instance of FlashBagAwareSessionInterface before calling the method. See phpstan/phpstan-symfony#324 (and referenced Symfony issues) for more details.

For the docs, I think we prefer this compact version as this will work for 99% of the Symfony applications and doesn't distract the code example from what we're actually wanting to showcase.