Include redux-mock-store in template deps

Author: alexandr-g

template.json

@@ -26,6 +26,7 @@
     "react-scripts": "3.3.0",
     "redux": "^4.0.5",
     "redux-devtools-extension": "^2.13.8",
+    "redux-mock-store": "^1.5.4",
     "typescript": "~3.7.2"
   },
   "scripts": {