- *Related to https://github.com/godotengine/godot/issues/74139.*

### Godot version

4.0.rc6

### System information

Fedora 37, GeForce RTX 4090 (NVIDIA 525.85.05)

### Issue description

VoxelGI does not preserve CameraAttributes across scene reloads. This leads to baked GI not containing light information (and only displaying ambient occlusion instead).

### After baking VoxelGI, before reloading the scene

*I increase exposure sensitivity to 3200 ISO, but this occurs with the default CameraAttributesPhysical settings too.*

![Screenshot_20230301_013751](https://user-images.githubusercontent.com/180032/222015520-81d2a50b-089b-4219-9680-c6539e09dfb2.png)

### After baking VoxelGI, saving then reloading the scene

*This is the result when running the project from the editor too.*

![Screenshot_20230301_013757](https://user-images.githubusercontent.com/180032/222015525-5048babe-d825-4421-bd4d-054cc8eee599.png)

### VoxelGI disabled (for comparison)

![Screenshot_20230301_013802](https://user-images.githubusercontent.com/180032/222015526-fbf3a3b0-2d53-4342-85e7-cd9f88d2df02.png)


### Steps to reproduce

- Follow [Physical light and camera units](https://docs.godotengine.org/en/latest/tutorials/3d/physical_light_and_camera_units.html) documentation to enable physical light and camera units in a project.
- Set up VoxelGI then bake it.

### Minimal reproduction project

[physical_light_camera_units.zip](https://github.com/godotengine/godot/files/10855923/physical_light_camera_units.zip)

ERR_FAIL_NULL(RenderingServer::get_singleton());
	RS::get_singleton()->free(probe);
}
void VoxelGI::set_probe_data(const Ref<VoxelGIData> &p_data) {
	if (p_data.is_valid()) {
		RS::get_singleton()->instance_set_base(get_instance(), p_data->get_rid());
	} else {
		RS::get_singleton()->instance_set_base(get_instance(), RID());
	}
	probe_data = p_data;
}
Ref<VoxelGIData> VoxelGI::get_probe_data() const {
	return probe_data;
}
void VoxelGI::set_subdiv(Subdiv p_subdiv) {
	ERR_FAIL_INDEX(p_subdiv, SUBDIV_MAX);
	subdiv = p_subdiv;
	update_gizmos();
}
VoxelGI::Subdiv VoxelGI::get_subdiv() const {
	return subdiv;
}
void VoxelGI::set_size(const Vector3 &p_size) {
	
	size = Vector3(MAX(1.0, p_size.x), MAX(1.0, p_size.y), MAX(1.0, p_size.z));
	update_gizmos();
}
Vector3 VoxelGI::get_size() const {