Fix wrapper generation for methods with reference-to-pointer arguments

[enlight]

Currently the native wrappers being generated for the following methods fail to compile:

• bool AIController::UseBlackboard(UBlackboardData* BlackboardAsset, UBlackboardComponent*& BlackboardComponent)
• bool UAbilityTask_VisualizeTargeting::BeginSpawningActor(UObject* WorldContextObject, TSubclassOf<AGameplayAbilityTargetActor> Class, AGameplayAbilityTargetActor*& SpawnedActor)
• void ProvideSingleActor(AActor* QuerierActor, AActor*& ResultingActor)

The managed wrappers for these methods compile, but do not work correctly.

In all these cases the issue is with the *& argument.