chore(package): update @vue/cli-service to version 4.1.2

Closes #113

Author: greenkeeper[bot]

package.json

@@ -49,7 +49,7 @@
     "@vue/cli-plugin-babel": "3.0.3",
     "@vue/cli-plugin-eslint": "3.0.0-beta.15",
     "@vue/cli-plugin-unit-jest": "3.0.3",
-    "@vue/cli-service": "3.0.3",
+    "@vue/cli-service": "4.1.2",
     "@vue/eslint-config-prettier": "3.0.0-rc.3",
     "@vue/test-utils": "1.0.0-beta.25",
     "babel-core": "7.0.0-bridge.0",