install mkdocs plugins

[River-Mochi]

Describe the bug

Please install following plugins so they can be used in the mkdocs.yml config.
some of these are missing which is causing the error on building the PR, messages are that pymdown is down

pip install pymdown-extensions
pip install mkdocs-git-revision-date-plugin
pip install mkdocs-autolinks-plugin
pip install mkdocs-awesome-pages-plugin

reference:

1. allows a collection of markdowns such as using github emoji, or other icons in the docs. https://facelessuser.github.io/pymdown-extensions/

2. Autolinks allows you to link to pages and images within MkDocs site without providing the entire relative path to the file in your document structure https://github.com/zachhannum/mkdocs-autolinks-plugin

3. Git-revision-date displays the last revision date of the current page of the documentation based on Git.
   https://github.com/zhaoterryy/mkdocs-git-revision-date-plugin
   then add this to footer of pages Page last revised on: {{ git_revision_date }}

4. awesome-pages allows you to customize how your pages show up the navigation of your MkDocs without having to configure the full structure inside your mkdocs.yml.
   Allows more fine control of this means that when ready, all the nav: could be moved out of YML and put into .pages (one .page for each folder).
   https://github.com/lukasgeiter/mkdocs-awesome-pages-plugin