chore(deps): update dependency typescript to v3

Author: renovate-bot

package.json

@@ -29,6 +29,6 @@
   "devDependencies": {
     "@types/graphql": "0.11.7",
     "@types/node": "8.5.2",
-    "typescript": "2.6.2"
+    "typescript": "3.1.3"
   }
 }