Discovery listeners registered via `LauncherConfig` or `Launcher` do not get notified about processed selectors

[marcphilipp]

Instances of LauncherDiscoveryListener registered via LauncherConfig (ServiceLoader or Builder) or directly on the Launcher are notified of all events except for the selectorProcessed method defined in the EngineDiscoveryListener super interface.

Deliverables

• Call selectorProcessed for all LauncherDiscoveryListener regardless how they're registered

[marcphilipp]

Fixed in 7926d81.