chore(package): update html-webpack-plugin to version 4.3.0

Closes #78

Author: greenkeeper[bot]

package.json

@@ -19,7 +19,7 @@
     "file-loader": "3.0.1",
     "fork-ts-checker-webpack-plugin": "^1.3.3",
     "html-loader": "0.5.5",
-    "html-webpack-plugin": "^3.2.0",
+    "html-webpack-plugin": "^4.3.0",
     "jasmine-core": "^3.4.0",
     "jquery": "^3.4.1",
     "json-loader": "0.5.7",