chore(package): update coveralls to version 3.0.12

Closes #28

Author: greenkeeper[bot]

package.json

@@ -44,7 +44,7 @@
   },
   "devDependencies": {
     "ava": "0.25.0",
-    "coveralls": "3.0.9",
+    "coveralls": "3.0.12",
     "minami": "^1.2.3",
     "nyc": "14.1.1",
     "standard": "14.3.1"