Add utility-types dep

package.json

@@ -35,7 +35,8 @@
     "prettier": "^1.16.4",
     "ts-jest": "^24.0.0",
     "ts-node": "^8.0.3",
-    "typescript": "^3.3.3333"
+    "typescript": "^3.3.3333",
+    "utility-types": "^3.6.1"
   },
   "jest": {
     "preset": "ts-jest",

yarn.lock

@@ -3925,6 +3925,11 @@ util.promisify@^1.0.0:
     define-properties "^1.1.2"
     object.getownpropertydescriptors "^2.0.3"
 
+utility-types@^3.6.1:
+  version "3.6.1"
+  resolved "https://registry.yarnpkg.com/utility-types/-/utility-types-3.6.1.tgz#14d0621888c906592d7544414b3762b33a657568"
+  integrity sha512-3MiRraWYaLnIjEbWHQEhuMlPIyjSVPZBlfvulm8xGMSs5nQrP0RiCCGJGvNCi2on8w8B7skRTNJUAGK+8PlbrQ==
+
 utils-merge@1.0.1:
   version "1.0.1"
   resolved "https://registry.yarnpkg.com/utils-merge/-/utils-merge-1.0.1.tgz#9f95710f50a267947b2ccc124741c1028427e713"