Merge pull request #12 from felixputera/greenkeeper/ts-jest-25.2.1

Upgrade ts-jest to v25.2.1

Author: felixputera

package-lock.json

@@ -29,7 +29,7 @@
     "lint-staged": "^9.5.0",
     "prettier": "^1.19.1",
     "prettier-package-json": "^2.1.0",
-    "ts-jest": "^24.2.0",
+    "ts-jest": "^25.2.1",
     "ts-node": "^8.5.4",
     "ttypescript": "^1.5.8",
     "typescript": "^3.7.2"