fix many PHP 8.4 compatibility issues

libs/Symfony/Component/EventDispatcher/ContainerAwareEventDispatcher.php

@@ -160,7 +160,7 @@ class ContainerAwareEventDispatcher extends EventDispatcher
      *
      * @throws \InvalidArgumentException if the service is not defined
      */
-    public function dispatch($eventName, Event $event = null)
+    public function dispatch($eventName, ?Event $event = null)
     {
         $this->lazyLoad($eventName);
 

libs/Symfony/Component/EventDispatcher/Debug/TraceableEventDispatcher.php

@@ -40,7 +40,7 @@ class TraceableEventDispatcher implements TraceableEventDispatcherInterface
      * @param Stopwatch                $stopwatch  A Stopwatch instance
      * @param LoggerInterface          $logger     A LoggerInterface instance
      */
-    public function __construct(EventDispatcherInterface $dispatcher, Stopwatch $stopwatch, LoggerInterface $logger = null)
+    public function __construct(EventDispatcherInterface $dispatcher, Stopwatch $stopwatch, ?LoggerInterface $logger = null)
     {
         $this->dispatcher = $dispatcher;
         $this->stopwatch = $stopwatch;
@@ -110,7 +110,7 @@ class TraceableEventDispatcher implements TraceableEventDispatcherInterface
     /**
      * {@inheritdoc}
      */
-    public function dispatch($eventName, Event $event = null)
+    public function dispatch($eventName, ?Event $event = null)
     {
         if (null === $event) {
             $event = new Event();

libs/Symfony/Component/EventDispatcher/Debug/WrappedListener.php

@@ -27,7 +27,7 @@ class WrappedListener
     private $stopwatch;
     private $dispatcher;
 
-    public function __construct($listener, $name, Stopwatch $stopwatch, EventDispatcherInterface $dispatcher = null)
+    public function __construct($listener, $name, Stopwatch $stopwatch, ?EventDispatcherInterface $dispatcher = null)
     {
         $this->listener = $listener;
         $this->name = $name;

libs/Symfony/Component/EventDispatcher/EventDispatcher.php

@@ -37,7 +37,7 @@ class EventDispatcher implements EventDispatcherInterface
      *
      * @api
      */
-    public function dispatch($eventName, Event $event = null)
+    public function dispatch($eventName, ?Event $event = null)
     {
         if (null === $event) {
             $event = new Event();

libs/Symfony/Component/EventDispatcher/EventDispatcherInterface.php

@@ -35,7 +35,7 @@ interface EventDispatcherInterface
      *
      * @api
      */
-    public function dispatch($eventName, Event $event = null);
+    public function dispatch($eventName, ?Event $event = null);
 
     /**
      * Adds an event listener that listens on the specified events.

libs/Symfony/Component/EventDispatcher/ImmutableEventDispatcher.php

@@ -38,7 +38,7 @@ class ImmutableEventDispatcher implements EventDispatcherInterface
     /**
      * {@inheritdoc}
      */
-    public function dispatch($eventName, Event $event = null)
+    public function dispatch($eventName, ?Event $event = null)
     {
         return $this->dispatcher->dispatch($eventName, $event);
     }