Update terser requirement from ~4.0.0 to ~4.3.1

Updates the requirements on [terser](https://github.com/fabiosantoscode/terser) to permit the latest version.
- [Release notes](https://github.com/fabiosantoscode/terser/releases)
- [Changelog](https://github.com/terser/terser/blob/master/CHANGELOG.md)
- [Commits](terser/terser@v4.0.0...v4.3.1)

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

package.json

@@ -125,7 +125,7 @@
     "svg-inline-loader": "~0.8.0",
     "svgo": "~1.2.2",
     "svgo-loader": "~2.2.0",
-    "terser": "~4.0.0",
+    "terser": "~4.3.1",
     "terser-webpack-plugin": "~2.0.0",
     "ts-node": "~8.2.0",
     "tsconfig-paths": "~3.8.0",