Update index.md

[nialloulton]

Updating the website with MMM-GPT information and link

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📚 Documentation preview 📚: https://pymc-marketing--433.org.readthedocs.build/en/433/

[nialloulton]

@twiecki

[codecov]

Codecov Report

All modified and coverable lines are covered by tests ✅

Project coverage is 90.83%. Comparing base (e9a854d) to head (9d757bd).
Report is 245 commits behind head on main.

Additional details and impacted files

@@           Coverage Diff           @@
##             main     #433   +/-   ##
=======================================
  Coverage   90.83%   90.83%           
=======================================
  Files          21       21           
  Lines        1920     1920           
=======================================
  Hits         1744     1744           
  Misses        176      176           

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[twiecki]

Let's reuse the text from #434.

[ricardoV94]

@nialloulton @twiecki is this one still relevant?

[juanitorduz]

@nialloulton I think we can close this one as it seems a duplicate by #434. we can always re-open it :) Is just we are doing some backlog cleaning 🙏