[Security] Fix docblock.

Author: derrabus

Core/Authentication/Token/Storage/TokenStorageInterface.php

@@ -30,7 +30,7 @@ public function getToken();
     /**
      * Sets the authentication token.
      *
-     * @param TokenInterface $token A TokenInterface token, or null if no further authentication information should be stored
+     * @param TokenInterface|null $token A TokenInterface token, or null if no further authentication information should be stored
      */
     public function setToken(TokenInterface $token = null);
 }