test: increase coverage for readfile with withFileTypes

According to the test coverage report a test case was missings checking
if an error is passed into the callback for readdir calls with
withFileTypes option.

PR-URL: https://github.com/nodejs/node/pull/23557


Reviewed-By: Anna Henningsen <anna@addaleax.net>
Reviewed-By: Colin Ihrig <cjihrig@gmail.com>
Reviewed-By: Gireesh Punathil <gpunathi@in.ibm.com>
Reviewed-By: James M Snell <jasnell@gmail.com>