test: remove string argument to strictEqual()

Removing string literal passed as argument to assert.strictEqual() in
order to print the expected value instead of the string. (First issue
assigned through Email by Rich Trott)

PR-URL: https://github.com/nodejs/node/pull/22718


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