fix(package): update joi to version 14.0.3

Closes #103

Author: greenkeeper[bot]

package.json

@@ -11,7 +11,7 @@
   "dependencies": {
     "contentful": "^7.0.4",
     "es6bindall": "^0.0.9",
-    "joi": "^13.7.0",
+    "joi": "^14.0.3",
     "when": "^3.7.8"
   },
   "devDependencies": {