Update dependency terser-webpack-plugin to v5.2.1

[renovate[bot]]

This PR contains the following updates:

Package	Change	Age	Adoption	Passing	Confidence
terser-webpack-plugin	5.2.0 -> 5.2.1

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Release Notes

webpack-contrib/terser-webpack-plugin

### [`v5.2.1`](https://togithub.com/webpack-contrib/terser-webpack-plugin/blob/master/CHANGELOG.md#​521-httpsgithubcomwebpack-contribterser-webpack-plugincomparev520v521-2021-09-02) [Compare Source](https://togithub.com/webpack-contrib/terser-webpack-plugin/compare/v5.2.0...v5.2.1)

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Configuration

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[elliotcourant]

bors r+

[bors[bot]]

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