N°6934 - Symfony 6.4 - upgrade Symfony bundles to 6.4 (#580)

* Update Symfony lib to version ~6.4.0
* Update code missing return type
* Add an iTop general configuration entry to store application secret (Symfony mandatory parameter)
* Use dependency injection in ExceptionListener & UserProvider classes

lib/symfony/framework-bundle/README.md

@@ -4,6 +4,11 @@ FrameworkBundle
 FrameworkBundle provides a tight integration between Symfony components and the
 Symfony full-stack framework.
 
+Sponsor
+-------
+
+Help Symfony by [sponsoring][1] its development!
+
 Resources
 ---------
 
@@ -11,3 +16,5 @@ Resources
  * [Report issues](https://github.com/symfony/symfony/issues) and
    [send Pull Requests](https://github.com/symfony/symfony/pulls)
    in the [main Symfony repository](https://github.com/symfony/symfony)
+
+[3]: https://symfony.com/sponsor