[Edit] Information Architecture

[AnamolR]

Description

This PR updates the existing Information Architecture entry in the uiux/concepts/ section to replace an internal link for "Tree Testing" text that directed to an external website with an internal link "https://www.codecademy.com/resources/docs/uiux/tree-testing"

Type of Change

Editing an existing entry (fixing a typo, bug, issues, etc)

Checklist

• All writings are my own.
• My edits follow 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 the updated content 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.

Issues Solved

closes #6660