[HttpKernel] Fix return type declarations

Author: nicolas-grekas

Container.php

@@ -444,8 +444,6 @@ public static function underscore($id)
 
     /**
      * Creates a service by requiring its factory file.
-     *
-     * @return object The service created by the file
      */
     protected function load($file)
     {

Dumper/DumperInterface.php

@@ -21,9 +21,7 @@ interface DumperInterface
     /**
      * Dumps the service container.
      *
-     * @param array $options An array of options
-     *
-     * @return string The representation of the service container
+     * @return string|array The representation of the service container
      */
     public function dump(array $options = []);
 }