Bump terser-webpack-plugin from 1.4.1 to 2.1.3 (#6654)
Bumps [terser-webpack-plugin](https://github.com/webpack-contrib/terser-webpack-plugin) from 1.4.1 to 2.1.3.
- [Release notes](https://github.com/webpack-contrib/terser-webpack-plugin/releases)
- [Changelog](https://github.com/webpack-contrib/terser-webpack-plugin/blob/master/CHANGELOG.md)
- [Commits](https://github.com/webpack-contrib/terser-webpack-plugin/compare/v1.4.1...v2.1.3)
Signed-off-by: dependabot-preview[bot] <support@dependabot.com>