enableReactPreset(callback = () => {}) {
        webpackConfig.enableReactPreset(callback);

        return this;
    }
If enabled, the react preset is added to Babel.

https://babeljs.io/docs/plugins/preset-react/

You can configure the preset by passing a callback:
```
Encore.enableReactPreset(function(options) {
    // https://babeljs.io/docs/babel-preset-react/#options
    options.development = !Encore.isProduction();
});
```

@param {OptionsCallback<object>} callback
@returns {Encore}