Update dependency eslint-loader to v3

[renovate[bot]]

This PR contains the following updates:

Package	Type	Update	Change
eslint-loader	devDependencies	major	2.2.1 -> 3.0.0

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Release Notes

webpack-contrib/eslint-loader

### [`v3.0.0`](https://togithub.com/webpack-contrib/eslint-loader/blob/master/CHANGELOG.md#​300httpsgithubcomwebpack-contribeslint-loadercomparev221v300-2019-08-24) [Compare Source](https://togithub.com/webpack-contrib/eslint-loader/compare/v2.2.1...v3.0.0)

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