chore(package): update codecov to version 3.6.1

Closes #299

Author: greenkeeper[bot]

package.json

@@ -42,7 +42,7 @@
     "babel-preset-react": "6.24.1",
     "babel-preset-stage-2": "6.24.1",
     "chai": "4.1.0",
-    "codecov": "2.2.0",
+    "codecov": "3.6.1",
     "enzyme": "^3.3.0",
     "enzyme-adapter-react-16": "^1.1.1",
     "eslint": "^3.19.0",