chore(deps): bump karma-webpack from 3.0.5 to 4.0.2

Bumps [karma-webpack](https://github.com/webpack-contrib/karma-webpack) from 3.0.5 to 4.0.2.
- [Release notes](https://github.com/webpack-contrib/karma-webpack/releases)
- [Changelog](https://github.com/webpack-contrib/karma-webpack/blob/master/CHANGELOG.md)
- [Commits](codymikol/karma-webpack@v3.0.5...v4.0.2)

Signed-off-by: dependabot-preview[bot] <support@dependabot.com>

Author: dependabot-preview[bot]