Update isArray.md

[Said-Suluk]

If we add a note like this, users can have a better experience

Description

I left a brief explanatory note here: 'console.log(Array.isArray([])); // Output: true console.log(Array.isArray(new Array(5))); // Output: true.' This way, users can get an idea about it. ### Issue Solved

Type of Change

• Adding a new entry
• Editing an existing entry (fixing a typo, bug, issues, etc)
• Updating the documentation

Checklist

• [+] All writings are my own.
• [+] My entry follows the Codecademy Docs style guide.
• [+] My changes generate no new warnings.
• [+] I have performed a self-review of my own writing and code.
• [+] I have checked my entry and corrected any misspellings.
• [+] I have made corresponding changes to the documentation if needed.
• [+] I have confirmed my changes are not being pushed from my forked main branch.
• [+] I have confirmed that I'm pushing from a new branch named after the changes I'm making.
• [+] I have linked any issues that are relevant to this PR in the Issues Solved section.

[CLAassistant]

All committers have signed the CLA.

[PragatiVerma18]

Closing this as this is not a valid issue, it was suggested by the author but isn't a major enhancement. The existing content is still easy to follow and understand.