react-select2-wrapper is using a deprecated lifecycle hook

![image](https://user-images.githubusercontent.com/6033/66579177-67050400-eb4a-11e9-9ef7-3ccf12c24589.png)

[getDerivedStateFromProps()](https://reactjs.org/docs/react-component.html#static-getderivedstatefromprops) looks like it can replace the use of `componentWillReceiveProps()` here