Provide default implementation of `centralManager(_:didFailToConnect:error:)` in `BaseGattProxyBearer`

[marczeugs]

Target

Library

Describe the feature

In BaseGattProxyBearer there is no implementation of centralManager(_:didFailToConnect:error:). This means that when a connection to the device fails (as it did in my case with a "MIC failure") and when using the GattBearer class, my logic got stuck as neither bearerDidOpen(_ bearer: Bearer) nor bearer(_ bearer: Bearer, didClose error: Error?) were ever called. Only by eventually manually implementing the didFailToConnect method in a class extending GattBearer and after a lot of trial and error did I see why the connection got stuck.

I am not sure if such an error should call the didClose callback, but I think it would be reasonable if BaseGattProxyBearer provided a default implementation that logs the error. If not, then GattBearer should at least mention that it is expected that code using the library handles certain callbacks itself.