Update dependency webpack-dev-server to v3.5.0

[renovate[bot]]

This PR contains the following updates:

Package	Type	Update	Change	References
webpack-dev-server	devDependencies	minor	3.4.1 -> 3.5.0	source

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Release Notes

webpack/webpack-dev-server

### [`v3.5.0`](https://togithub.com/webpack/webpack-dev-server/blob/master/CHANGELOG.md#​350httpsgithubcomwebpackwebpack-dev-servercomparev341v350-2019-05-31) [Compare Source](https://togithub.com/webpack/webpack-dev-server/compare/v3.4.1...v3.5.0) ##### Bug Fixes - add client code for `electron-renderer` target ([#​1935](https://togithub.com/webpack/webpack-dev-server/issues/1935)) ([9297988](https://togithub.com/webpack/webpack-dev-server/commit/9297988)) - add client code for `node-webkit` target ([#​1942](https://togithub.com/webpack/webpack-dev-server/issues/1942)) ([c6b2b1f](https://togithub.com/webpack/webpack-dev-server/commit/c6b2b1f)) ##### Features - **server:** `onListening` option ([#​1930](https://togithub.com/webpack/webpack-dev-server/issues/1930)) ([61d0cdf](https://togithub.com/webpack/webpack-dev-server/commit/61d0cdf)) - **server:** add callback support for invalidate ([#​1900](https://togithub.com/webpack/webpack-dev-server/issues/1900)) ([cd218ef](https://togithub.com/webpack/webpack-dev-server/commit/cd218ef)) - **server:** add `WEBPACK_DEV_SERVER` env variable ([#​1929](https://togithub.com/webpack/webpack-dev-server/issues/1929)) ([856169e](https://togithub.com/webpack/webpack-dev-server/commit/856169e)) ##### [3.4.1](https://togithub.com/webpack/webpack-dev-server/compare/v3.4.0...v3.4.1) (2019-05-17) ##### Bug Fixes - add none and warning to clientLogLevel ([#​1901](https://togithub.com/webpack/webpack-dev-server/issues/1901)) ([0ae9be8](https://togithub.com/webpack/webpack-dev-server/commit/0ae9be8)) - broken hot reload ([#​1903](https://togithub.com/webpack/webpack-dev-server/issues/1903)) ([6a444cd](https://togithub.com/webpack/webpack-dev-server/commit/6a444cd))

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