Force proxy update with functional component App

[mcallisto]

Using hooks and FunctionalComponent, I changed in App.scala from
@react class App extends Component { ... }
to
@react object App {...}

Consequently I had to change in Main.scala from

    if (LinkingInfo.developmentMode) {
      hot.initialize()
      App.componentConstructor // required to force proxy update
    }
    
    AppRegistry.registerComponent("$name$", () => {
      App
    })

to

    if (LinkingInfo.developmentMode) {
      hot.initialize()
      App.component // @todo check if it is working
//      App.componentConstructor // required to force proxy update
    }

    AppRegistry.registerComponent("$name$", () => {
      App.component
    })

It compiles, but is it correct to force proxy update?