Merge pull request #839 from reactjs/renovate/react-16.x

Update dependency @types/react to v16.8.20

Author: Daniel15

src/React.Sample.Mvc4/package-lock.json

@@ -7,7 +7,7 @@
     "lint:ts": "tsc"
   },
   "devDependencies": {
-    "@types/react": "16.8.19",
+    "@types/react": "16.8.20",
     "@types/react-dom": "16.8.4",
     "@types/reactstrap": "8.0.1",
     "typescript": "3.5.1"