DOCS: Smaller cards on homepage

[tkknight]

DRAFT - DO NOT REVIEW

🚀 Pull Request

Description

The large cards on the Iris doc homepage are now condensed meaning less scrolling for users when reading the homepage.

The card descriptions in the .rst are much easier to read (and thus maintain) too.

Inspiration for this taken from the GeoVista Docs, credit to @bjlittle for this 🤜 🤛

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Codecov Report

✅ All modified and coverable lines are covered by tests.
✅ Project coverage is 90.43%. Comparing base (36a5bc3) to head (125681e).
⚠️ Report is 1 commits behind head on main.

Additional details and impacted files

@@           Coverage Diff           @@
##             main    #6886   +/-   ##
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  Coverage   90.43%   90.43%           
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  Files          91       91           
  Lines       24839    24839           
  Branches     4656     4656           
=======================================
  Hits        22463    22463           
  Misses       1608     1608           
  Partials      768      768           

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