fix docstring example rendering

[OriolAbril]

closes #373

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📚 Documentation preview 📚: https://causalpy--376.org.readthedocs.build/en/376/

[codecov]

Codecov Report

All modified and coverable lines are covered by tests ✅

Project coverage is 85.60%. Comparing base (f6fd97c) to head (cd181dc).
Report is 103 commits behind head on main.

Additional details and impacted files

@@           Coverage Diff           @@
##             main     #376   +/-   ##
=======================================
  Coverage   85.60%   85.60%           
=======================================
  Files          22       22           
  Lines        1716     1716           
=======================================
  Hits         1469     1469           
  Misses        247      247           

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[drbenvincent]

Thanks. This is great. I guess in the future we can have a discussion about whether we want to use numpydoc. But for now, this is great :)