test: fix flaky test-benchmark-misc

Allow zero results for short benchmark test.

PR-URL: https://github.com/nodejs/node/pull/17686


Reviewed-By: Colin Ihrig <cjihrig@gmail.com>
Reviewed-By: Anatoli Papirovski <apapirovski@mac.com>
Reviewed-By: James M Snell <jasnell@gmail.com>