Skip preload test under asan

Just like the other preload tests with startup failures, this may
cause leaks.

Author: nikic

ext/opcache/tests/preload_parse_error.phpt

@@ -9,6 +9,7 @@ opcache.preload={PWD}/preload_parse_error.inc
 <?php
 require_once('skipif.inc');
 if (PHP_OS_FAMILY == 'Windows') die('skip Preloading is not supported on Windows');
+if (getenv('SKIP_ASAN')) die('xfail Startup failure leak');
 ?>
 --FILE--
 OK