process: refactor execution

• Removed unreachable code of the `evalModule()` function as an early
error is thrown when the `print` parameter is a truthy value.
• Make use of the nullish coalescing operator.

PR-URL: https://github.com/nodejs/node/pull/40664


Reviewed-By: Antoine du Hamel <duhamelantoine1995@gmail.com>
Reviewed-By: Luigi Pinca <luigipinca@gmail.com>
Reviewed-By: Minwoo Jung <nodecorelab@gmail.com>