Correctly calculate last parens in ruleset as mixin param

[AndreasHogstrom]

Which issue # if any, does this resolve?
#128

Please check one:

• New tests created for this change
• Tests updated for this change

This PR:

• Adds new API
• Extends existing API, backwards-compatible
• Introduces a breaking change
• Fixes a bug

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The following code found in lib/LessParser.js:95 always returns the first closing parenthesis rather than the last, as indicated by the variable name.

const lastParenIndex = tokens.findIndex((t) => t[0] === ')');

This breaks the parsing when there are multiple closing parenthesis in the list of tokens.

[codecov-io]

Codecov Report

Merging #132 into master will decrease coverage by 0.01%.
The diff coverage is 100%.

@@            Coverage Diff             @@
##           master     #132      +/-   ##
==========================================
- Coverage   96.49%   96.47%   -0.02%     
==========================================
  Files           8        8              
  Lines         228      227       -1     
==========================================
- Hits          220      219       -1     
  Misses          8        8

Impacted Files	Coverage Δ
lib/LessParser.js	99.13% <100%> (ø)	⬆️
lib/nodes/inline-comment.js	100% <0%> (ø)	⬆️

---

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[shellscape]

Thank you for contributing a fix!

@jwilsson this looks good to me. please give this a look

[jwilsson]

Looks good to me too.

Thanks for the fix!

[drserg]

Hi guys! Could you please release this fix? Thanks a lot in advance