Add quickstart example usage to module docstring

[lucaferranti]

I create new packages rarely enough that I generally don't remeber by heart what command to run. I had the same issue with PkgTemplates.jl and one thing I really liked is that I could do ?PkgTemplate in the REPL and it would kindly remind me how to use it (to be fair, that was just dumping the Pkg README in the terminal, hence I had to do a bit of scrolling).

This PR adds the quickstart example usage to the module docstring, so that people can do ?BestieTemplate to get a quick reminder of how to use it.

Checklist

• I am following the contributing guidelines

• Tests are passing

• Lint workflow is passing

• Docs were updated and workflow is passing

• CHANGELOG.md was updated

[lucaferranti]

(not sure if this even needs a changelog update, but I can add one if needed)

[codecov]

Codecov Report

All modified and coverable lines are covered by tests ✅

Project coverage is 100.00%. Comparing base (7281bcb) to head (0775e71).
Report is 1 commits behind head on main.

Additional details and impacted files

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  Coverage   100.00%   100.00%           
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  Files            4         4           
  Lines          104       104           
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  Hits           104       104           

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[abelsiqueira]

Thanks, this is great!
There is no need for a changelog update.