chore(package): update @octokit/rest to version 15.14.0

Author: greenkeeper[bot]

package.json

@@ -38,7 +38,7 @@
     "version-changelog": "^3.1.0"
   },
   "dependencies": {
-    "@octokit/rest": "^15.2.6",
+    "@octokit/rest": "^15.14.0",
     "is-binary-buffer": "^2.0.0"
   }
 }