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[boopathi]

• removes immutable-js because it fails with memory limit 4g error.

[codecov]

Codecov Report

Merging #495 into master will increase coverage by 0.03%.
The diff coverage is n/a.

@@            Coverage Diff            @@
##           master    #495      +/-   ##
=========================================
+ Coverage   82.56%   82.6%   +0.03%     
=========================================
  Files          35      35              
  Lines        2627    2627              
  Branches      927     927              
=========================================
+ Hits         2169    2170       +1     
+ Misses        280     279       -1     
  Partials      178     178

Impacted Files	Coverage Δ
packages/babel-plugin-minify-simplify/src/index.js	80.72% <0%> (+0.12%)	⬆️

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