doc: update process.execArg example to be more useful

PR-URL: #52412
Reviewed-By: Antoine du Hamel <duhamelantoine1995@gmail.com>
Reviewed-By: Raz Luvaton <rluvaton@gmail.com>

Author: JakobJingleheimer

doc/api/process.md

@@ -1711,15 +1711,13 @@ the script name. These options are useful in order to spawn child processes with
 the same execution environment as the parent.
 
 ```bash
-node --harmony script.js --version
+node --icu-data-dir=./foo --require ./bar.js script.js --version
 ```
 
 Results in `process.execArgv`:
 
-<!-- eslint-disable semi -->
-
-```js
-['--harmony']
+```json
+["--icu-data-dir=./foo", "--require", "./bar.js"]
 ```
 
 And `process.argv`: