Merge webpack optimisation configs

[WearyMonkey]

Issue

#4120

What I did

Merges the webpack optimisation configs.

[storybook-safe-bot]

	Fails
🚫	PR is not labeled with one of: ["cleanup","BREAKING CHANGE","feature request","bug","documentation","maintenance","dependencies:update","dependencies","other"]

Generated by 🚫 dangerJS

[codecov]

Codecov Report

Merging #4121 into master will increase coverage by 0.01%.
The diff coverage is 100%.

@@            Coverage Diff            @@
##           master   #4121      +/-   ##
=========================================
+ Coverage   40.59%   40.6%   +0.01%     
=========================================
  Files         483     483              
  Lines        5747    5748       +1     
  Branches      770     770              
=========================================
+ Hits         2333    2334       +1     
  Misses       3042    3042              
  Partials      372     372

Impacted Files	Coverage Δ
lib/core/src/server/mergeConfigs.js	100% <100%> (ø)	⬆️

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