Update dependency typescript to v3

Author: renovate-bot

package.json

@@ -21,7 +21,7 @@
     "now": "9.2.7",
     "npm-run-all": "4.1.2",
     "ts-node": "4.1.0",
-    "typescript": "2.6.2"
+    "typescript": "3.1.1"
   },
   "dependencies": {
     "apollo-errors": "1.9.0",

yarn.lock

@@ -2704,9 +2704,9 @@ type-is@~1.6.15:
     media-typer "0.3.0"
     mime-types "~2.1.15"
 
-typescript@2.6.2:
-  version "2.6.2"
-  resolved "https://registry.yarnpkg.com/typescript/-/typescript-2.6.2.tgz#3c5b6fd7f6de0914269027f03c0946758f7673a4"
+typescript@3.1.1:
+  version "3.1.1"
+  resolved "https://registry.yarnpkg.com/typescript/-/typescript-3.1.1.tgz#3362ba9dd1e482ebb2355b02dfe8bcd19a2c7c96"
 
 uid-number@^0.0.6:
   version "0.0.6"