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/error-handler/ErrorEnhancer/UndefinedFunctionErrorEnhancer.php

@@ -19,9 +19,6 @@ use Symfony\Component\ErrorHandler\Error\UndefinedFunctionError;
  */
 class UndefinedFunctionErrorEnhancer implements ErrorEnhancerInterface
 {
-    /**
-     * {@inheritdoc}
-     */
     public function enhance(\Throwable $error): ?\Throwable
     {
         if ($error instanceof FatalError) {
@@ -42,7 +39,7 @@ class UndefinedFunctionErrorEnhancer implements ErrorEnhancerInterface
 
         $prefix = 'Call to undefined function ';
         $prefixLen = \strlen($prefix);
-        if (0 !== strpos($message, $prefix)) {
+        if (!str_starts_with($message, $prefix)) {
             return null;
         }