minor #39903 [FrameworkBundle] do not fail when MercureBundle is not installed (xabbuh)

This PR was merged into the 5.3-dev branch.

Discussion
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[FrameworkBundle] do not fail when MercureBundle is not installed

| Q             | A
| ------------- | ---
| Branch?       | 5.x
| Bug fix?      | yes
| New feature?  | no
| Deprecations? | no
| Tickets       |
| License       | MIT
| Doc PR        |

Commits
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8cdbdcb1c9 do not fail when MercureBundle is not installed

Author: chalasr

DependencyInjection/FrameworkExtension.php

@@ -2257,13 +2257,11 @@ private function registerNotifierConfiguration(array $config, ContainerBuilder $
             }
         }
 
-        if (class_exists(MercureTransportFactory::class)) {
-            if (!class_exists(MercureBundle::class)) {
-                throw new \LogicException('The MercureBundle is not registered in your application. Try running "composer require symfony/mercure-bundle".');
-            }
-
+        if (class_exists(MercureTransportFactory::class) && class_exists(MercureBundle::class)) {
             $container->getDefinition($classToServices[MercureTransportFactory::class])
                 ->replaceArgument('$publisherLocator', new ServiceLocatorArgument(new TaggedIteratorArgument('mercure.publisher', null, null, true)));
+        } elseif (class_exists(MercureTransportFactory::class)) {
+            $container->removeDefinition($classToServices[MercureTransportFactory::class]);
         }
 
         if (isset($config['admin_recipients'])) {