fix: upgrade redux-thunk from 2.4.1 to 2.4.2

Snyk has created this PR to upgrade redux-thunk from 2.4.1 to 2.4.2.

See this package in npm:
https://www.npmjs.com/package/redux-thunk

See this project in Snyk:
https://app.snyk.io/org/jamesdbloom/project/16eaafd0-fedd-4627-8f06-e3d0bfeaba02?utm_source=github&utm_medium=referral&page=upgrade-pr

Author: snyk-bot

package-lock.json

@@ -40,7 +40,7 @@
     "redux": "^4.2.0",
     "redux-form": "^7.4.3",
     "redux-form-material-ui": "^4.3.3",
-    "redux-thunk": "^2.4.1"
+    "redux-thunk": "^2.4.2"
   },
   "scripts": {
     "start": "react-scripts start",