Add Cross-Site Scripting (XSS) entry

[DanSmith8011]

Description

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.

[mamtawardhani]

Hey @DanSmith8011, this PR Doesn't trace back to any issues. So here are a few changes that we can do first and see how they appear:

1. The path given to the file is incorrect, shouldn't this be under javascript concepts?
2. The entry DOES NOT follow the Codecademy Guidelines, please go through the PR raised or the Contribution Guide to understand the requirements.

Let me know once these changes have been done 😄