chore: remove readthedocs link and update docs index
Description
We've moved off of ReadTheDocs for the documentation of the site. This updates the reference in the main project README to remove that. This also standardizes the main documentation index to match what's published on https://docs.gitlab.com/ee/integration/glab/
Related Issues
Resolves #[issue_number]
How has this been tested?
Screenshots (if appropriate):
Types of changes
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Bug fix (non-breaking change which fixes an issue) -
New feature (non-breaking change which adds functionality) -
Breaking change (fix or feature that would cause existing functionality to change) -
Documentation -
Chore (Related to CI or Packaging to platforms)