[HttpKernel] fixed default ESI cache strategy when the page does not contain ESIs

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

@@ -54,6 +54,11 @@ class EsiResponseCacheStrategy implements EsiResponseCacheStrategyInterface
      */
     public function update(Response $response)
     {
+        // if we only have one Response, do nothing
+        if (1 === count($this->ttls)) {
+            return;
+        }
+
         if (!$this->cacheable) {
             $response->headers->set('Cache-Control', 'no-cache, must-revalidate');