Mark OSS tests as skipped if there's any infra issues

Summary: These fail when there's internet conenctivity issues. Given they fail in large batches a retry doesn't seem like a worthwhile approach (as each framework is effecitvely a retry for downloading phpunit).

Also, removed __FILE__ from the error message as it always said utils.php :p

Reviewed By: @ptarjan

Differential Revision: D1476671