### Godot version

4.0-rc6

### System information

Fedora 37, Mesa Intel ADL GT2

### Issue description

Code that works as expected at runtime fails with Nil references to (assigned) exported vars in the editor:

![tool_global_position_error](https://user-images.githubusercontent.com/364501/222031460-ffb1ecbd-5175-4a42-8470-25285ba5f821.png)


### Steps to reproduce

Try to access the `global_position` of a `Node3D` that's assigned to an exported var.

See that it works at runtime.

See that it errors in the editor with:

> Invalid get index 'global_position' (on base: 'Nil').

### Minimal reproduction project

[tool_test.zip](https://github.com/godotengine/godot/files/10856640/tool_test.zip)

}
			}
			resources_found.erase(r.ptr());
		} break;
		default: {
		}
	}
	return false;
}
void EditorPropertyResource::_resource_changed(const Ref<Resource> &p_resource) {
	Resource *r = Object::cast_to<Resource>(get_edited_object());
	if (r) {
		
		HashSet<Resource *> resources_found;
		resources_found.insert(r);
		bool found = _find_recursive_resources(p_resource, resources_found);
		if (found) {
			EditorNode::get_singleton()->show_warning(TTR("Recursion detected, unable to assign resource to property."));
			emit_changed(get_edited_property(), Ref<Resource>());
			update_property();
			return;
		}
	}
	
	
	bool is_script = false;
	Ref<Script> s = p_resource;
	if (get_edited_object() && s.is_valid() && get_edited_property() == CoreStringNames::get_singleton()->_script) {
		is_script = true;
		InspectorDock::get_singleton()->store_script_properties(get_edited_object());