Fix legacy class palceholder definitions for static analysis

Author: ausi

Loader/AnnotationClassLoader.php

@@ -19,7 +19,7 @@ class_exists(AttributeClassLoader::class);
     /**
      * @deprecated since Symfony 6.4, to be removed in 7.0, use {@link AttributeClassLoader} instead
      */
-    class AnnotationClassLoader
+    abstract class AnnotationClassLoader extends AttributeClassLoader
     {
     }
 }

Loader/AnnotationDirectoryLoader.php

@@ -19,7 +19,7 @@ class_exists(AttributeDirectoryLoader::class);
     /**
      * @deprecated since Symfony 6.4, to be removed in 7.0, use {@link AttributeDirectoryLoader} instead
      */
-    class AnnotationDirectoryLoader
+    class AnnotationDirectoryLoader extends AttributeDirectoryLoader
     {
     }
 }

Loader/AnnotationFileLoader.php

@@ -19,7 +19,7 @@ class_exists(AttributeFileLoader::class);
     /**
      * @deprecated since Symfony 6.4, to be removed in 7.0, use {@link AttributeFileLoader} instead
      */
-    class AnnotationFileLoader
+    class AnnotationFileLoader extends AttributeFileLoader
     {
     }
 }