Update dependency ts-jest to v22.4.6

Author: renovate-bot

package.json

@@ -35,7 +35,7 @@
     "@types/jest": "22.1.3",
     "codecov": "3.0.0",
     "jest": "22.3.0",
-    "ts-jest": "22.0.4",
+    "ts-jest": "22.4.6",
     "tslint": "5.9.1",
     "typedoc": "0.9.0",
     "typescript": "2.6.2"