chore(package): update copy-webpack-plugin to version 6.0.0

Closes #163

Author: greenkeeper[bot]

package.json

@@ -20,7 +20,7 @@
             "set NODE_ENV=development & webpack-dev-server --host 0.0.0.0 --progress --colors --content-base dist/  --watch --hot --inline --config  webpack.config.js"
     },
     "devDependencies": {
-        "copy-webpack-plugin": "4.5.3",
+        "copy-webpack-plugin": "6.0.0",
         "webpack": "4.29.6",
         "webpack-cli": "3.1.2",
         "webpack-dev-server": "3.2.1"