Using Ruby On Rails For Your Backend: Restructure the lesson content to address lint issues

[goran1010]

Because

This lesson had numerous lint errors and required both slight restructuring of the content and couple of smaller fixes.

This PR

• Fix formatting of the ordered list
• Fix order of the main lesson sections
• Number of sentences had to be edited to address various lint issues

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