chore: update TypeScript dependency (fuse-box#1409)

Author: NN---

package-lock.json

@@ -107,7 +107,7 @@
     "run-sequence": "^1.2.2",
     "should": "^11.1.0",
     "stylus": "^0.54.5",
-    "typescript": "^3.1.0-dev.20180804",
+    "typescript": "^3.1.0",
     "uglify-es": "^3.3.9",
     "uglify-js": "^3.4.7",
     "validate-commit-msg": "^2.14.0",
@@ -146,4 +146,4 @@
   },
   "typings": "index.d.ts",
   "version": "3.6.0-next.13"
-}
+}