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/polyfill-php81/Php81.php

@@ -1,37 +0,0 @@
-<?php
-
-/*
- * This file is part of the Symfony package.
- *
- * (c) Fabien Potencier <fabien@symfony.com>
- *
- * For the full copyright and license information, please view the LICENSE
- * file that was distributed with this source code.
- */
-
-namespace Symfony\Polyfill\Php81;
-
-/**
- * @author Nicolas Grekas <p@tchwork.com>
- *
- * @internal
- */
-final class Php81
-{
-    public static function array_is_list(array $array): bool
-    {
-        if ([] === $array || $array === array_values($array)) {
-            return true;
-        }
-
-        $nextKey = -1;
-
-        foreach ($array as $k => $v) {
-            if ($k !== ++$nextKey) {
-                return false;
-            }
-        }
-
-        return true;
-    }
-}