Use shared babel-preset file for transform

[KevinGrandon]

This uses our shared babel preset for tests so we don't need to duplicate a list of presets.

Fixes #68

[codecov]

Codecov Report

Merging #71 into master will decrease coverage by 0.04%.
The diff coverage is 0%.

@@            Coverage Diff             @@
##           master      #71      +/-   ##
==========================================
- Coverage   67.82%   67.77%   -0.05%     
==========================================
  Files          66       66              
  Lines        1411     1412       +1     
  Branches      307      308       +1     
==========================================
  Hits          957      957              
  Misses        400      400              
- Partials       54       55       +1

Impacted Files	Coverage Δ
build/babel-preset.js	83.33% <0%> (-16.67%)	⬇️

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[KevinGrandon]

!merge