child_process: handling fork( path, undefined / null, obj )

[shobhitchittora]

Closes: #20749

Checklist

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

NOTE: Run test using - python ./tools/test.py parallel/test-child-process-fork-options.js

Affected subsystem(s)

child_process / fork