Merge pull request #6695 from auth0/davidpatrick-patch-nodeyarn

Update node & yarn

Author: erjohnson

package.json

@@ -12,8 +12,8 @@
     "*.md": "markdownlint"
   },
   "engines": {
-    "node": "8.9.4",
-    "yarn": "1.3.2"
+    "node": "~8.11.3",
+    "yarn": "^1.4.0"
   },
   "devDependencies": {
     "commander": "^2.8.1",