### 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)

StringName travel = travel_request;
	travel_request = StringName();
	if (!playing) {
		_start(p_state_machine);
	}
	ERR_FAIL_COND_V(!p_state_machine->states.has(travel), false);
	ERR_FAIL_COND_V(!p_state_machine->states.has(current), false);
	if (current == travel) {
		return !p_is_allow_transition_to_self;
	}
	Vector<StringName> new_path;
	Vector2 current_pos = p_state_machine->states[current].position;
	Vector2 target_pos = p_state_machine->states[travel].position;
	bool found_route = false;
	HashMap<StringName, AStarCost> cost_map;
	List<int> open_list;