test: fix args passed to strictEqual

The third argument passed to asert.strictEqual() displays the message
passed as third argument and does not report the difference between
actual and expected if the test is failing.
Hence, the third argument has been removed.

PR-URL: https://github.com/nodejs/node/pull/21584


Reviewed-By: Rich Trott <rtrott@gmail.com>
Reviewed-By: Anna Henningsen <anna@addaleax.net>
Reviewed-By: Colin Ihrig <cjihrig@gmail.com>
Reviewed-By: Luigi Pinca <luigipinca@gmail.com>
Reviewed-By: James M Snell <jasnell@gmail.com>
Reviewed-By: Trivikram Kamat <trivikr.dev@gmail.com>