fix(package): update @octokit/rest to version 16.0.3

Closes #64

Author: greenkeeper[bot]

package.json

@@ -25,7 +25,7 @@
     "nyc": "^13.1.0"
   },
   "dependencies": {
-    "@octokit/rest": "^15.17.0",
+    "@octokit/rest": "^16.0.3",
     "sinon": "^6.3.5"
   },
   "engines": {