[HttpKernel] fixed a volatile test

Author: fabpot

Tests/HttpCache/HttpCacheTest.php

@@ -606,7 +606,7 @@ public function testAssignsDefaultTtlWhenResponseHasNoFreshnessInformationAndAft
         $this->assertTraceContains('miss');
         $this->assertTraceContains('store');
         $this->assertEquals('Hello World', $this->response->getContent());
-        $this->assertRegExp('/s-maxage=2/', $this->response->headers->get('Cache-Control'));
+        $this->assertRegExp('/s-maxage=(?:2|3)/', $this->response->headers->get('Cache-Control'));
 
         $this->request('GET', '/');
         $this->assertHttpKernelIsNotCalled();