minor #11981 Fix @return docs on HttpCache::restoreResponseBody() (znerol)

This PR was submitted for the master branch but it was merged into the 2.3 branch instead (closes #11981).

Discussion
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Fix @return docs on HttpCache::restoreResponseBody()

Commits
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37dc57b Fix @return docs on HttpCache::restoreResponseBody()

src/Symfony/Component/HttpKernel/HttpCache/HttpCache.php

@@ -601,8 +601,6 @@ class HttpCache implements HttpKernelInterface, TerminableInterface
      *
      * @param Request  $request  A Request instance
      * @param Response $response A Response instance
-     *
-     * @return Response A Response instance
      */
     private function restoreResponseBody(Request $request, Response $response)
     {