Prevent usage of the return value of ReactDOM.render (react/no-render…

…-return-value)

Fixes: standard/standard#1568

eslintrc.json

@@ -22,6 +22,7 @@
     "react/no-danger-with-children": "error",
     "react/no-deprecated": "error",
     "react/no-direct-mutation-state": "error",
+    "react/no-render-return-value": "error",
     "react/no-is-mounted": "error",
     "react/no-find-dom-node": "error",
     "jsx-quotes": ["error", "prefer-single"],