minor #24186 [EventDispatcher] Removed unnecessary getDefinition() call from RegisterListenersPass (derrabus)

This PR was merged into the 3.3 branch.

Discussion
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[EventDispatcher] Removed unnecessary getDefinition() call from RegisterListenersPass

| Q             | A
| ------------- | ---
| Branch?       | 3.3
| Bug fix?      | yes
| New feature?  | no
| BC breaks?    | no
| Deprecations? | no
| Tests pass?   | yes
| Fixed tickets | none
| License       | MIT
| Doc PR        | N/A

In `RegisterListenersPass`, the definition of each tagged listener service is pulled from the builder although it is never used. This PR removes the line of code where this happens.

Commits
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d1f7024 Removed unnecessary getDefinition() call.

Author: fabpot

src/Symfony/Component/EventDispatcher/DependencyInjection/RegisterListenersPass.php

@@ -62,8 +62,6 @@ public function process(ContainerBuilder $container)
         $definition = $container->findDefinition($this->dispatcherService);
 
         foreach ($container->findTaggedServiceIds($this->listenerTag, true) as $id => $events) {
-            $def = $container->getDefinition($id);
-
             foreach ($events as $event) {
                 $priority = isset($event['priority']) ? $event['priority'] : 0;