`register_handler` on `Client` and `Component` is too constrained, the closure only needs to live as long as the `Dispatcher`.
Not sure how to resolve this issue with lifetimes, but it would make register_handler
a lot more useful.
Do not update/delete: Banner broadcast message test data
Do not update/delete: Notification broadcast message test data
Not sure how to resolve this issue with lifetimes, but it would make register_handler
a lot more useful.