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/dependency-injection/Loader/Configurator/Traits/ArgumentTrait.php

@@ -18,7 +18,7 @@ trait ArgumentTrait
      *
      * @return $this
      */
-    final public function args(array $arguments): self
+    final public function args(array $arguments): static
     {
         $this->definition->setArguments(static::processValue($arguments, true));
 
@@ -28,12 +28,9 @@ trait ArgumentTrait
     /**
      * Sets one argument to pass to the service constructor/factory method.
      *
-     * @param string|int $key
-     * @param mixed      $value
-     *
      * @return $this
      */
-    final public function arg($key, $value): self
+    final public function arg(string|int $key, mixed $value): static
     {
         $this->definition->setArgument($key, static::processValue($value, true));