Merge branch '6.0' into 6.1

* 6.0:
  [Semaphore] fix tests
  [HttpClient] fix destructing CurlResponse
  [Cache] Fix connecting to Redis via a socket file
  [DependencyInjection][FrameworkBundle] Fix using PHP 8.1 enum as parameters
  [PropertyAccessor] Add missing TypeError catch
  [HttpKernel] Fixed error count by log not displayed in WebProfilerBundle
  Added `kernel.event_listener` to the default list of behavior describing tags, fixing AsEventListener attribute not working on decorators.
  [HttpKernel] Fix FileLinkFormatter with empty xdebug.file_link_format
  [WebProfilerBundle] Fixes weird spacing in log message context/trace output
  [Notifier] fix Microsoft Teams webhook url
  [FrameworkBundle] Fix log channel of TagAwareAdapter
  [Postmark] ensure only a single tag can be used with Postmark
  [Mailer] allow Mailchimp to handle multiple TagHeader's
  [HttpClient] Fix Content-Length header when possible
  [Routing] AnnotationDirectoryLoader::load() may return null
  [DependencyInjection] Don't dump polyfilled classes in preload script

Author: nicolas-grekas

Loader/AnnotationDirectoryLoader.php

@@ -25,7 +25,7 @@ class AnnotationDirectoryLoader extends AnnotationFileLoader
     /**
      * @throws \InvalidArgumentException When the directory does not exist or its routes cannot be parsed
      */
-    public function load(mixed $path, string $type = null): RouteCollection
+    public function load(mixed $path, string $type = null): ?RouteCollection
     {
         if (!is_dir($dir = $this->locator->locate($path))) {
             return parent::supports($path, $type) ? parent::load($path, $type) : new RouteCollection();

Tests/Loader/AnnotationDirectoryLoaderTest.php

@@ -99,6 +99,14 @@ public function testLoadFileIfLocatedResourceIsFile()
         $this->loader->load(__DIR__.'/../Fixtures/AnnotatedClasses/FooClass.php');
     }
 
+    public function testLoadAbstractClass()
+    {
+        $this->reader->expects($this->never())->method('getClassAnnotation');
+        $this->reader->expects($this->never())->method('getMethodAnnotations');
+
+        $this->loader->load(__DIR__.'/../Fixtures/AnnotatedClasses/AbstractClass.php');
+    }
+
     private function expectAnnotationsToBeReadFrom(array $classes)
     {
         $this->reader->expects($this->exactly(\count($classes)))