Merge branch '5.4' into 6.0

* 5.4:
  [Notifier] composer.json cleanup
  [HttpKernel] AbstractSessionListener should not override the cache lifetime for private responses
  [DependencyInjection] Shared private services becomes public after a public service is accessed
  [DI] Fix undefined class in test

Author: nicolas-grekas

composer.json

@@ -21,9 +21,6 @@
         "symfony/notifier": "^5.4|^6.0",
         "symfony/polyfill-mbstring": "^1.0"
     },
-    "require-dev": {
-        "symfony/event-dispatcher": "^5.4|^6.0"
-    },
     "autoload": {
         "psr-4": { "Symfony\\Component\\Notifier\\Bridge\\Discord\\": "" },
         "exclude-from-classmap": [