fix: package.json & yarn.lock to reduce vulnerabilities

The following vulnerabilities are fixed with an upgrade:
- https://snyk.io/vuln/SNYK-JS-INFLIGHT-6095116

Author: snyk-bot

package.json

@@ -20,7 +20,7 @@
     "react-hook-form-input": "^1.1.10",
     "react-redux": "^7.2.0",
     "react-router-dom": "^5.2.0",
-    "react-scripts": "3.4.1",
+    "react-scripts": "4.0.0",
     "redux-thunk": "^2.3.0",
     "typescript": "3.9.3"
   },