Intermediate HTML/CSS - Signup form project: discourage JS use

[fabulousgk]

Because

Currently the project suggests using JS to validate the passwords as an optional excersise. However, we have been removing these sorts of things to discourage rabbit trails.

This PR

• Rewords last step to discourage JS checking
• Fixes some lining things

Issue

Closes #27271

Additional Information

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

[MaoShizhong]

🙏 Thank you as always!