Fix for problem when service discovery process gets stuck

[vladiulianbogdan]

This is related to this issue.

What was happening is that if a disconnect occurs right after the discoverServices(nil) call and the discovery response was not yet received, future discoverServices calls will never return anything because the remainingServicesDiscoveryRequest is unbalanced (it was incremented but it was never decremented because of the disconnect event).

It is the same problem for discoverCharacteristics and discoverIncludedServices.

[CLAassistant]

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