Add failing test for #2823

[stefanfisk]

Here's a failing test for #2823.

Fixes: #2823

[codecov-io]

Codecov Report

Merging #2824 (1e9ddc6) into master (3ea5e18) will increase coverage by 0.01%.
The diff coverage is 100.00%.

@@            Coverage Diff             @@
##           master    #2824      +/-   ##
==========================================
+ Coverage   93.20%   93.22%   +0.01%     
==========================================
  Files         177      177              
  Lines        1795     1800       +5     
  Branches      317      318       +1     
==========================================
+ Hits         1673     1678       +5     
  Misses        105      105              
  Partials       17       17              

Impacted Files	Coverage Δ
src/lib/substituteClassApplyAtRules.js	94.66% <100.00%> (+0.18%)	⬆️

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[RobinMalfait]

Hey! Thank you for your PR! I love that you pushed a failing test!
Much appreciated! 🙏

I pushed the fixes directly to your branch.

Thanks!

[stefanfisk]

The pleasure's mine - thanks for a great library!