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/config/ConfigCacheFactoryInterface.php

@@ -25,8 +25,6 @@ interface ConfigCacheFactoryInterface
      *
      * @param string   $file     The absolute cache file path
      * @param callable $callable The callable to be executed when the cache needs to be filled (i. e. is not fresh). The cache will be passed as the only parameter to this callback
-     *
-     * @return ConfigCacheInterface
      */
-    public function cache(string $file, callable $callable);
+    public function cache(string $file, callable $callable): ConfigCacheInterface;
 }