minor #53119 Code updates (javiereguiluz)

This PR was squashed before being merged into the 7.1 branch.

Discussion
----------

Code updates

| Q             | A
| ------------- | ---
| Branch?       | 7.1
| Bug fix?      | no
| New feature?  | no
| Deprecations? | no
| Issues        | -
| License       | MIT

For your consideration, this PR includes several simplifications/improvements to code as suggested by PHPStorm inspection tools.

Commits
-------

e29033486d Code updates

Author: nicolas-grekas

Console/Descriptor/JsonDescriptor.php

@@ -323,7 +323,7 @@ private function getContainerAliasData(Alias $alias): array
     private function getEventDispatcherListenersData(EventDispatcherInterface $eventDispatcher, array $options): array
     {
         $data = [];
-        $event = \array_key_exists('event', $options) ? $options['event'] : null;
+        $event = $options['event'] ?? null;
 
         if (null !== $event) {
             foreach ($eventDispatcher->getListeners($event) as $listener) {

Console/Descriptor/XmlDescriptor.php

@@ -501,7 +501,7 @@ private function getContainerParameterDocument(mixed $parameter, ?array $depreca
 
     private function getEventDispatcherListenersDocument(EventDispatcherInterface $eventDispatcher, array $options): \DOMDocument
     {
-        $event = \array_key_exists('event', $options) ? $options['event'] : null;
+        $event = $options['event'] ?? null;
         $dom = new \DOMDocument('1.0', 'UTF-8');
         $dom->appendChild($eventDispatcherXML = $dom->createElement('event-dispatcher'));