Changelog Description

Add a CI action to trigger MK Docs deployment on creating new tags.
when testing the CI action manually (trigger from Action tab manually on GH), it will generate a dummy-build version that will be deleted as soon as a tag is created.

Additional Notes

This PR add some cosmetics:

1. update light and dark mode icons.
2. move requirments file to root location of the repo to avoid moving it along with the docs build.

Testing notes:

1. You can trigger from actions tab on GH gh cli

   gh workflow run deploy_mkdocs.yml --ref feature/ci-mkdocs-with-enhancements