Bump terser-webpack-plugin from 2.3.6 to 3.0.0

Bumps [terser-webpack-plugin](https://github.com/webpack-contrib/terser-webpack-plugin) from 2.3.6 to 3.0.0.
- [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/v2.3.6...v3.0.0)

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

package.json

@@ -98,7 +98,7 @@
     "serve-static": "^1.14.0",
     "shx": "^0.3.2",
     "sinon": "^9.0.0",
-    "terser-webpack-plugin": "^2.0.1",
+    "terser-webpack-plugin": "^3.0.0",
     "typescript": "^3.8.3",
     "url-polyfill": "^1.1.5",
     "walk": "^2.3.9",