Update dependency clean-webpack-plugin to v4

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This PR contains the following updates:

Package	Change	Age	Adoption	Passing	Confidence
clean-webpack-plugin	^3.0.0 -> ^4.0.0

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Release Notes

johnagan/clean-webpack-plugin

### [`v4.0.0`](https://togithub.com/johnagan/clean-webpack-plugin/releases/tag/v4.0.0) [Compare Source](https://togithub.com/johnagan/clean-webpack-plugin/compare/v3.0.0...v4.0.0) Changes - Added support for NodeJS 14 - Added support for webpack 5 Breaking changes: - Dropped support for NodeJS 8 - Dropped support for webpack 3

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