### Godot version

v4.0.beta12.mono.official [3c9bf4bc2]

### System information

Windows 10

### Issue description

When using GetTree().ChangeScene (or GetTree().ReloadCurrentScene), the orphan node count in Monitors goes up by the number of nodes in the target scene.

This effect is amplified when running a scene that has lots of nodes.


I've also tested this in the previous beta (v4.0.beta11.mono.official [91713ced8]) and confirmed the issue didn't exist there.

### Steps to reproduce

1. Run the included Minimal Reproduction Project.
2. Open the Debugger/Monitors tab.
3. Press "Space" to load Scene2.tcsn (2 Nodes).
 - Orphan nodes increases by 2.
5. Press "Space" to load Scene1.tcsn (3 Nodes).
 - Orphan nodes increases by 3.

### Minimal reproduction project

[MRP.zip](https://github.com/godotengine/godot/files/10415860/MRP.zip)

_call_idle_callbacks();
#ifdef TOOLS_ENABLED
#ifndef _3D_DISABLED
	if (Engine::get_singleton()->is_editor_hint()) {
		
		String env_path = GLOBAL_GET(SNAME("rendering/environment/defaults/default_environment"));
		env_path = env_path.strip_edges(); 
		String cpath;
		Ref<Environment> fallback = get_root()->get_world_3d()->get_fallback_environment();
		if (fallback.is_valid()) {
			cpath = fallback->get_path();
		}
		if (cpath != env_path) {
			if (!env_path.is_empty()) {
				fallback = ResourceLoader::load(env_path);
				if (fallback.is_null()) {
					
					ProjectSettings::get_singleton()->set("rendering/environment/defaults/default_environment", "");
				}
			} else {
				fallback.unref();
			}
			get_root()->get_world_3d()->set_fallback_environment(fallback);
		}
	}
#endif 
#endif 
	return _quit;
}
void SceneTree::process_timers(double p_delta, bool p_physics_frame) {