Accommodate annotation on Props class

[jedahu]

Given this component definition:

@react
object Foo {
  @something
  case class Props(a: Int, b: String)

  val component = FunctionalComponent[Props} { ... }
}

The react macro doesn't match case class Props because of the something annotation, and generates,

  def apply(props: Props)

instead of the expected,

  def apply[..$tparams](...$paramssWithoutChildren)...

This change fixes this, but only for functional component definitions, because they are the only ones I have tested so far.

[shadaj]

Thanks for the PR @jedahu! The changes look good to me, but looks like you'll have to run scalafmt once.