test : lint and few minor fixes

Lint and some other minor fixes. Files modified :

• test/parallel/test-assert.js
• test/parallel/test-whatwg-url-setters.js

Checklist

• make -j4 test (UNIX), or vcbuild test (Windows) passes
• tests and/or benchmarks are included
• commit message follows commit guidelines

Affected core subsystem(s)

test