Method in DialogueViewBase
Called by the DialogueRunner to signal that the dialogue has ended, and no more lines will be delivered.
This method is called after the last piece of content (that is, lines, options or commands) finished running.
This method is a good place to perform tasks like dismissing on-screen dialogue UI (for example, turning off a letterboxing effect, or hiding dialogue UI elements.)
The default implementation of this method does nothing.