Add run notebook script

[juanitorduz]

Attempt to run notebooks on the CI.

It was not so easy to add to the CI so we can manually run this script before the releases.

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📚 Documentation preview 📚: https://pymc-marketing--624.org.readthedocs.build/en/624/

[codecov]

Codecov Report

All modified and coverable lines are covered by tests ✅

Project coverage is 91.61%. Comparing base (e2dba27) to head (519d70b).

Additional details and impacted files

@@           Coverage Diff           @@
##             main     #624   +/-   ##
=======================================
  Coverage   91.61%   91.61%           
=======================================
  Files          22       22           
  Lines        2277     2277           
=======================================
  Hits         2086     2086           
  Misses        191      191           

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[juanitorduz]

890ac2f Fails because of the nb -> html step, which we do not need. I will continue in a different path: do it via a custom simple script

[juanitorduz]

I'll close this PR as I wanna see how it is done for the core pymc notebooks as pointed out by @OriolAbril 🙏