Installation Overview: Emphasise specifics and instructions are in the next lesson

[MaoShizhong]

Because

It's common for people to stop and ask questions about OS options or even try to install things themselves when they've just read the Installations Overview lesson before moving on to the Installations lesson itself. The overview lesson does mention about instructions coming in the next lesson but it's not as visible as it can be.

Recently there have been a fair few confused new learners in the community because of this, e.g. not knowing about specific Linux distro/version support which isn't explicitly stated until the next lesson.

The Chromebook information can also be moved to its own subsection to be consistent with the other OS options, as opposed to being an end paragraph to the lesson overview list.

This PR

• Fixes reasonable linting issues
• Moves verbiage on purpose of this lesson + instructions coming in next lesson to a more visible note box outside of the learning objectives
• Moves Chromebook information to its own subsection instead of being inside the learning objects section

Issue

Closes #XXXXX

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

[wise-king-sullyman]

🔥