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/css-selector/Node/NodeInterface.php

@@ -21,11 +21,9 @@ namespace Symfony\Component\CssSelector\Node;
  *
  * @internal
  */
-interface NodeInterface
+interface NodeInterface extends \Stringable
 {
     public function getNodeName(): string;
 
     public function getSpecificity(): Specificity;
-
-    public function __toString(): string;
 }