fix: Keep math functions together

[wongjn]

Follow up to #894

[codecov-io]

Codecov Report

Merging #895 into master will decrease coverage by 0.00%.
The diff coverage is 100.00%.

@@            Coverage Diff             @@
##           master     #895      +/-   ##
==========================================
- Coverage   97.28%   97.28%   -0.01%     
==========================================
  Files         118      118              
  Lines        3459     3458       -1     
  Branches     1041     1040       -1     
==========================================
- Hits         3365     3364       -1     
  Misses         86       86              
  Partials        8        8              

Impacted Files	Coverage Δ
packages/postcss-convert-values/src/index.js	100.00% <100.00%> (ø)

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[anikethsaha]

can you add some tests if possible .

[alexander-akait]

Thanks!

/cc @anikethsaha

[anikethsaha]

🎉

[anikethsaha]

thanks 👍