Forms and Data Handling: Change incorrect link in Knowledge Check

[Anshuman-Jha-01]

Because

This PR updates an incorrect link under Knowledge Check section of Forms and Data Handling topic.

This PR

• Fixes the incorrect link which leads to a page about SQL Injection in the final question in the Knowledge Check section to a link that leads to a section about escaping HTML characters.

Issue

Closes #29515

Pull Request Requirements

• I have thoroughly read and understand The Odin Project curriculum contributing guide
• The title of this PR follows the location of change: brief description of change format, e.g. Intro to HTML and CSS lesson: Fix link text
• The Because section summarizes the reason for this PR
• The This PR section has a bullet point list describing the changes in this PR
• If this PR addresses an open issue, it is linked in the Issue section
• If any lesson files are included in this PR, they have been previewed with the Markdown preview tool to ensure it is formatted correctly
• If any lesson files are included in this PR, they follow the Layout Style Guide

[KevinMulhern]

Thanks @Anshuman-Jha-01