Fix for crash when director is reset during scene transition

[rh101]

Describe your changes

If the application is closed during certain scene transitions, such as TransitionFade, the application will crash in Node::~Node() since the incoming scene is still active (Node::_running == true). This is due to the Node::onExit() not being called on the incoming scene in the transition.

This PR address that issue, by making it the responsibility of the transition to ensure that the incoming scene is correctly deactivated (Node::_running == false) if it detects that the Director has been reset, meaning that the app is shutting down.

Issue ticket number and link

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[rh101]

Incorrect base branch. Will create another PR