chore(package): update mini-css-extract-plugin to version 0.8.1

Closes #34

Author: greenkeeper[bot]

package.json

@@ -7,7 +7,7 @@
     "css-loader": "3.0.0",
     "cypress": "^3.2.0",
     "http-server": "^0.11.1",
-    "mini-css-extract-plugin": "^0.7.0",
+    "mini-css-extract-plugin": "^0.8.1",
     "npm-run-all": "^4.1.5",
     "serve": "^11.0.0",
     "svelte": "^2.16.1",