chore(package): update fixpack to version 3.0.4

Closes #81

Author: greenkeeper[bot]

package.json

@@ -18,7 +18,7 @@
     "eslint-plugin-promise": "^3.5.0",
     "eslint-plugin-standard": "^3.0.1",
     "execa": "^0.10.0",
-    "fixpack": "^2.3.1",
+    "fixpack": "^3.0.4",
     "nyc": "^11.0.1"
   },
   "directories": {