Update motivation_and_mindset.md

[yeldarx]

Because

I have added a paragraph about public and university libraries to provide additional information on study environments.

This PR

• Added a paragraph about public and university libraries, emphasizing their serene and comfortable study environments.
• Mentioned that some libraries operate 24/7, providing uninterrupted study opportunities.
• Highlighted the sense of productivity that comes from studying alongside others.

Issue

Additional Information

No additional information to provide.

Pull Request Requirements

• I have thoroughly read and understand The Odin Project 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

[wise-king-sullyman]

Reminding people that libraries are a thing seems like a great idea!

Thanks!