Update introduction_to_grid.md

[aswain009]

Because

updating the links for the "Remember how much fun you had solving the card layout in this exercise?" section of the https://www.theodinproject.com/lessons/node-path-intermediate-html-and-css-introduction-to-grid page

This PR

-Fixed the broken image and image link on the https://www.theodinproject.com/lessons/node-path-intermediate-html-and-css-introduction-to-grid page

Issue

Closes #XXXXX

Does not close an open issues that I am aware of.

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

[CouchofTomato]

There seem to be more changes in here than you indicate above. Can you give more information on the changes you want to make here.