Update dependency ts-jest to v22.4.6

Author: renovate-bot

package.json

@@ -25,7 +25,7 @@
     "@types/minimist": "1.2.0",
     "jest": "22.1.4",
     "bot-tester": "3.4.2",
-    "ts-jest": "22.0.2",
+    "ts-jest": "22.4.6",
     "ts-node": "4.1.0",
     "tslint": "5.9.1",
     "typescript": "2.7.2"