### Godot version

v4.1.rc2.official [46424488e]

### System information

Godot v4.1.rc2 - Windows 10.0.22621 - Vulkan (Forward+) - dedicated NVIDIA GeForce RTX 3060 (NVIDIA; 31.0.15.3623) - AMD Ryzen 7 5700G with Radeon Graphics (16 Threads)

### Issue description

When setting the AnimationTree to active, Godot crashes.

### Steps to reproduce

https://github.com/godotengine/godot/assets/46705245/dbe5eb81-1357-43e8-ac80-a4eb97eea9fc

### Minimal reproduction project

[Crash.zip](https://github.com/godotengine/godot/files/11945826/Crash.zip)

if (updating_transitions) {
		return;
	}
	ERR_FAIL_COND(p_from == end_node || p_to == start_node);
	ERR_FAIL_COND(p_from == p_to);
	ERR_FAIL_COND(!_can_connect(p_from));
	ERR_FAIL_COND(!_can_connect(p_to));
	ERR_FAIL_COND(p_transition.is_null());
	for (int i = 0; i < transitions.size(); i++) {
		ERR_FAIL_COND(transitions[i].from == p_from && transitions[i].to == p_to);
	}
	updating_transitions = true;
	Transition tr;
	tr.from = p_from;
	tr.to = p_to;
	tr.transition = p_transition;
	tr.transition->connect("advance_condition_changed", callable_mp(this, &AnimationNodeStateMachine::_tree_changed), CONNECT_REFERENCE_COUNTED);
	transitions.push_back(tr);
	updating_transitions = false;
}
Ref<AnimationNodeStateMachineTransition> AnimationNodeStateMachine::get_transition(int p_transition) const {