test: add test for fs.promises.lchmod

To increase test coverage for fs.promises by adding a test for
lchmod.

PR-URL: https://github.com/nodejs/node/pull/20584


Reviewed-By: James M Snell <jasnell@gmail.com>
Reviewed-By: Ruben Bridgewater <ruben@bridgewater.de>
Reviewed-By: Richard Lau <riclau@uk.ibm.com>
Reviewed-By: Michael Dawson <michael_dawson@ca.ibm.com>