chore(package): update html-webpack-plugin to version 4.0.1

Closes #30

Author: greenkeeper[bot]

package.json

@@ -64,7 +64,7 @@
     "eslint-plugin-react-hooks": "^2.3.0",
     "express": "^4.17.1",
     "file-loader": "^5.0.2",
-    "html-webpack-plugin": "^3.2.0",
+    "html-webpack-plugin": "^4.0.1",
     "husky": "^3.1.0",
     "jest": "^24.9.0",
     "less": "^3.10.3",