message: Update package.json
  Changing react-scripts to 3.1.2 resolves this error.
diff: "react-dom": "^16.9.0",
  "react-dropzone": "^10.1.8",
  "react-router-dom": "^5.0.1",
  - "react-scripts": "3.1.1",
  + "react-scripts": "3.1.2",
  "start": "^5.1.0",
  "typescript": "3.6.2",
  "yarn": "^1.19.0",
  