test: added a few new test files

[JoshuaKGoldberg]

PR Checklist

• Addresses an existing open issue: makes progress on 🛠 Tooling: Add more unit testing around src/setup #471
• That issue was marked as status: accepting prs
• Steps in CONTRIBUTING.md were taken

Overview

Adds a trio of test files. Doesn't exhaustively increase coverage (I want to leave that open to future contributors!), but hopefully gets us to a nicer green coverage badge in the README.md

[github-actions]

PR Compliance Checks

Thank you for your Pull Request! We have run several checks on this pull request in order to make sure it's suitable for merging into this project. The results are listed in the following section.

Issue Reference

In order to be considered for merging, the pull request description must refer to a specific issue number. This is described in our Contributing Guide. We are closing this pull request for now but you can update the pull request description and reopen the pull request.
The check is looking for a phrase similar to: "Fixes #XYZ" or "Resolves #XYZ" where XYZ is the issue number that this PR is meant to address.

[codecov]

Codecov Report

Merging #536 (d87a09e) into main (9d626e6) will increase coverage by 0.27%.
The diff coverage is 100.00%.

❗ Current head d87a09e differs from pull request most recent head 3010582. Consider uploading reports for the commit 3010582 to get more accurate results

@@            Coverage Diff             @@
##             main     #536      +/-   ##
==========================================
+ Coverage   87.09%   87.36%   +0.27%     
==========================================
  Files          55       55              
  Lines        2936     2936              
  Branches      120      120              
==========================================
+ Hits         2557     2565       +8     
+ Misses        376      368       -8     
  Partials        3        3              

Impacted Files	Coverage Δ
src/shared/getDefaultSettings.ts	61.53% <ø> (ø)
src/shared/inputs.ts	100.00% <100.00%> (ø)

... and 1 file with indirect coverage changes

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[github-actions]

🎉 This is included in version v1.28.19 🎉

The release is available on:

• GitHub releases
• npm package (@latest dist-tag)

Cheers! 📦🚀