Update ext/curl/tests/curl_upkeep_001.phpt

Co-authored-by: Christoph M. Becker <cmbecker69@gmx.de>

Author: adoy

ext/curl/tests/curl_upkeep_001.phpt

@@ -4,6 +4,7 @@ curl_upkeep() function
 curl
 --SKIPIF--
 <?php
+if (getenv("SKIP_ONLINE_TESTS")) die("skip online test");
 if (curl_version()['version_number'] < 0x073e00) die('skip requires curl >= 7.62.0');
 ?>
 --FILE--