### Godot version

v4.2.dev3.official [013e8e3af]

### System information

Godot v4.2.dev3 - macOS 13.4.1 - Vulkan (Forward+) - integrated Apple M1 - Apple M1 (8 Threads)

### Issue description

The content is empty. In the list `<Select Importer> `should be preselected, if possible. 
Or directly show the settings for "Animation Library" (check first selection).


![Bildschirmfoto 2023-08-22 um 01 29 44](https://github.com/godotengine/godot/assets/41921395/8300a756-ff54-4310-a0ad-04ad9525aeb9)


### Steps to reproduce

1. Project
2. Project Settings
3. Import Defaults 

https://github.com/godotengine/godot/assets/41921395/cb263c7d-27f0-4053-a555-0ed03ac7ef2a



### Minimal reproduction project

N/A
if (settings->importer.is_valid()) {
		Dictionary modified;
		for (const KeyValue<StringName, Variant> &E : settings->values) {
			if (E.value != settings->default_values[E.key]) {
				modified[E.key] = E.value;
			}
		}
		if (modified.size()) {
			ProjectSettings::get_singleton()->set("importer_defaults/" + settings->importer->get_importer_name(), modified);
		} else {
			ProjectSettings::get_singleton()->set("importer_defaults/" + settings->importer->get_importer_name(), Variant());
		}
	}
}
void ImportDefaultsEditor::_update_importer() {
	List<Ref<ResourceImporter>> importer_list;
	ResourceFormatImporter::get_singleton()->get_importers(&importer_list);
	Ref<ResourceImporter> importer;
	for (const Ref<ResourceImporter> &E : importer_list) {
		if (E->get_visible_name() == importers->get_item_text(importers->get_selected())) {
			importer = E;
			break;
		}
	}
	settings->properties.clear();
	settings->values.clear();