Fix broken links to pseudo-selectors in advanced_selectors.md

[abeeto]

Because

Changes the previous broken links to pseudo selectors from css-tricks.com to new links in line with their restructured almanac page.

This PR

Issue

Closes #XXXXX

Additional Information

PS: My first commit/PR to TOP, great work everyone!

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]

Thanks for the PR @abeeto. Looks like this would close #28876 but that's already been assigned to the issue author. As per our contributing guide, please check for existing or duplicate issues/PRs before opening your own to avoid doing work that may end up being rejected. For example if an issue is already open for a bug, you are welcome to comment on that issue requesting to be assigned (but this doesn't guarantee you will be the one assigned, so please don't open a PR unless you've actually been assigned first).

Since the existing issue has been assigned already, I will close this PR without merging.