Update react-helmet to the latest version 🚀 (#1519)

* fix(package): update react-helmet to version 6.0.0

* chore(package): update lockfile package-lock.json

Co-authored-by: greenkeeper[bot] <23040076+greenkeeper[bot]@users.noreply.github.com>

Author: greenkeeper[bot]

package-lock.json

@@ -64,7 +64,7 @@
     "react-dnd": "10.0.2",
     "react-dnd-html5-backend": "10.0.2",
     "react-dom": "16.13.1",
-    "react-helmet": "5.2.1",
+    "react-helmet": "6.0.0",
     "react-json-view": "^1.19.1",
     "react-redux": "5.1.2",
     "react-router": "5.1.2",