Update dependency terser-webpack-plugin to v5

Author: renovate[bot]

package.json

@@ -41,13 +41,13 @@
     "raw-loader": "^4.0.1",
     "sade": "^1.7.3",
     "style-loader": "^1.1.4",
-    "terser-webpack-plugin": "^2.3.5",
+    "terser-webpack-plugin": "^5.0.0",
     "ts-loader": "^7.0.0",
     "typescript": "^3.8.3",
     "webpack": "^4.42.1"
   },
   "devDependencies": {
-    "@types/terser-webpack-plugin": "^2.2.0",
+    "@types/terser-webpack-plugin": "^5.0.0",
     "ava": "^3.7.0",
     "esm": "^3.2.25",
     "execa": "^4.0.0",