chore(deps): update dependency webpack to v4.39.0

Author: renovate-bot

package.json

@@ -69,7 +69,7 @@
     "prettier": "1.18.2",
     "ts-jest": "24.0.2",
     "typescript": "3.5.3",
-    "webpack": "4.38.0",
+    "webpack": "4.39.0",
     "webpack-cli": "3.3.6"
   },
   "jest": {