Contain all content in a given page within landmarks

[ChrisXKeroack]

Describe the bug
Contain all content in a given page within landmarks

To Reproduce
Steps to reproduce the behavior:

1. https://openfl.readthedocs.io/en/latest/index.html
2. Examine the code, and/or run the browser plugin for aXe Devtools

notice:

and versions expendable section in sidebar, are not within landmarks on the page

Expected behavior

should be part of a footer landmark and expandable section of sidebar should be within the element for the sidebar

Screenshots
If applicable, add screenshots to help explain your problem.

Desktop:
This issue is not OS or browser specific, but for tracking purposes, testing was done on Win11, in Edge Version 114.0.1823.58 (Official build) (64-bit).

Smartphone:
This issue is not device, OS, or browser specific.

Additional context
This is an accessibility issue, please annotate this bug with the 'accessibility' label.

[fstrr]

This is an issue with the Read The Docs platform.