bug #46956 [FrameworkBundle] Allow to specify null for exception mapping configuration values (andrew-demb)

This PR was squashed before being merged into the 5.4 branch.

Discussion
----------

[FrameworkBundle] Allow to specify `null` for exception mapping configuration values

| Q             | A
| ------------- | ---
| Branch?       | 5.4
| Bug fix?      | yes
| New feature?  | no <!-- please update src/**/CHANGELOG.md files -->
| Deprecations? | no <!-- please update UPGRADE-*.md and src/**/CHANGELOG.md files -->
| Tickets       |
| License       | MIT
| Doc PR        |
<!--
Replace this notice by a short README for your feature/bugfix.
This will help reviewers and should be a good start for the documentation.

Additionally (see https://symfony.com/releases):
 - Always add tests and ensure they pass.
 - Bug fixes must be submitted against the lowest maintained branch where they apply
   (lowest branches are regularly merged to upper ones so they get the fixes too.)
 - Features and deprecations must be submitted against the latest branch.
 - Changelog entry should follow https://symfony.com/doc/current/contributing/code/conventions.html#writing-a-changelog-entry
 - Never break backward compatibility (see https://symfony.com/bc).
-->
`null` should be allowed because it is stated as allowed in the configuration info [1][2]
Marked as bugfix due to an existing mismatch between config description and behavior.

[1] https://github.com/symfony/symfony/blob/a2f27add28f7c2c61ef4cfb4e97833509ced0fc0/src/Symfony/Bundle/FrameworkBundle/DependencyInjection/Configuration.php#L1219-L1220
[2] https://github.com/symfony/symfony/blob/a2f27add28f7c2c61ef4cfb4e97833509ced0fc0/src/Symfony/Bundle/FrameworkBundle/DependencyInjection/Configuration.php#L1227-L1228

Commits
-------

1de8f3a9ff [FrameworkBundle] Allow to specify `null` for exception mapping configuration values

Author: fabpot

EventListener/ErrorListener.php

@@ -33,8 +33,14 @@ class ErrorListener implements EventSubscriberInterface
     protected $controller;
     protected $logger;
     protected $debug;
+    /**
+     * @var array<class-string, array{log_level: string|null, status_code: int<100,599>|null}>
+     */
     protected $exceptionsMapping;
 
+    /**
+     * @param array<class-string, array{log_level: string|null, status_code: int<100,599>|null}> $exceptionsMapping
+     */
     public function __construct($controller, LoggerInterface $logger = null, bool $debug = false, array $exceptionsMapping = [])
     {
         $this->controller = $controller;