MultiProvider should emit distinct events

[PenguinDan]

Because we currently don't handle EventDetails, the MultiProvider does not implement the distinctUntilChanged operator on the events that it emits.

The specification mentions that OnConfigurationChanged emitted by child providers should always re-emit as shown here https://openfeature.dev/specification/appendix-a/#multi-provider-status.

Because OnConfigurationChanged is an object, having a distinctUntilChanged operator would prevent the multiple emits of a child OnConfigurationChanged.

There is an open PR for the event details here #170

[PenguinDan]

Opting out of the distinctUntilChanged note I added on the MultiProvider to just forward events from Child providers

If a child provider is emitting events, I think it makes sense to just forward them without applying additional filters