Update react-dnd to the latest version 🚀 (#1033)

* chore(package): update react-dnd to version 7.4.0

* chore(package): update react-dnd-html5-backend to version 7.4.0

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

Author: greenkeeper[bot]

package-lock.json

@@ -78,8 +78,8 @@
     "prop-types": "15.7.2",
     "query-string": "6.4.0",
     "react": "16.8.4",
-    "react-dnd": "7.3.2",
-    "react-dnd-html5-backend": "7.2.0",
+    "react-dnd": "7.4.0",
+    "react-dnd-html5-backend": "7.4.0",
     "react-dom": "16.8.4",
     "react-router": "4.4.0",
     "react-router-dom": "4.4.0",