[4.4] Add missing @return annotations

Author: nicolas-grekas

OptionsResolver.php

@@ -1084,6 +1084,8 @@ public function offsetExists($option)
     /**
      * Not supported.
      *
+     * @return void
+     *
      * @throws AccessException
      */
     public function offsetSet($option, $value)
@@ -1094,6 +1096,8 @@ public function offsetSet($option, $value)
     /**
      * Not supported.
      *
+     * @return void
+     *
      * @throws AccessException
      */
     public function offsetUnset($option)