Consider moving the resposibility of cloning debug configs from IDebugEngine to IDebugConfig

[enlight]

As in remove IDebugEngine::cloneConfig() and add IDebugConfig::clone(). This would make it simpler to clone a debug config since you wouldn't have to find the relevant debug engine. Though the only thing that ever actually clones debug configs right now is DebugConfigManager, so this is probably not super important.