[REQ] [PHP-Symfony] Encurage Symfony 5 bundle directory structure best practices

[lukadschaak]

Is your feature request related to a problem? Please describe.

When working with the PHP-Symfony Generator, the output was not as i expected. Especially because there was already a PR who updated the generator to PHP 8.1 and Symfony 5: #11810

I wish it to be more like explained here: https://symfony.com/doc/current/bundles/best_practices.html#directory-structure

Describe the solution you'd like

Refactor the code of PhpSymfonyServerCodegen.java.

Describe alternatives you've considered

Add an generator config option that enables the Symfony 5 directory structure.

Additional context

Already started a PR: #13014