chore(deps): update dependency webpack-dev-server to v4

[renovate[bot]]

This PR contains the following updates:

Package	Change	Age	Adoption	Passing	Confidence
webpack-dev-server	^3.11.2 -> ^4.0.0

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Release Notes

webpack/webpack-dev-server

### [`v4.0.0`](https://togithub.com/webpack/webpack-dev-server/blob/master/CHANGELOG.md#​400-httpsgithubcomwebpackwebpack-dev-servercomparev400-rc1v400-2021-08-18) [Compare Source](https://togithub.com/webpack/webpack-dev-server/compare/v3.11.2...v4.0.0)

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Configuration

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