### Godot version

v4.0.beta17.mono.official [c40020513]

### System information

Window 11, Forward+, GTX 1060

### Issue description

Adding two theme variations in a row result to a  crash.

https://user-images.githubusercontent.com/93253123/217037249-1ce1d56d-beb6-4435-83ad-9f8a07fe0e96.mp4



### Steps to reproduce

1. Create a project.
2. Create a theme.
3. Double click to go in the theme editor.
4. Click on manage items buttons.
5. In the add type field type a name to add a type.
6. type another name to add a second type.
7. Crash.

### Minimal reproduction project

[ThemeVariationCrash.zip](https://github.com/godotengine/godot/files/10665863/ThemeVariationCrash.zip)

Button *button = memnew(Button);
	button->set_text(p_text);
	button->set_theme_type_variation(SNAME("InspectorActionButton"));
	button->set_h_size_flags(SIZE_SHRINK_CENTER);
	return button;
}
String EditorInspector::get_selected_path() const {
	return property_selected;
}
void EditorInspector::_parse_added_editors(VBoxContainer *current_vbox, EditorInspectorSection *p_section, Ref<EditorInspectorPlugin> ped) {
	for (const EditorInspectorPlugin::AddedEditor &F : ped->added_editors) {
		EditorProperty *ep = Object::cast_to<EditorProperty>(F.property_editor);
		current_vbox->add_child(F.property_editor);
		if (ep) {
			ep->object = object;
			ep->connect("property_changed", callable_mp(this, &EditorInspector::_property_changed).bind(false));
			ep->connect("property_keyed", callable_mp(this, &EditorInspector::_property_keyed));
			ep->connect("property_deleted", callable_mp(this, &EditorInspector::_property_deleted), CONNECT_DEFERRED);
			ep->connect("property_keyed_with_value", callable_mp(this, &EditorInspector::_property_keyed_with_value));
			ep->connect("property_checked", callable_mp(this, &EditorInspector::_property_checked));
			ep->connect("property_pinned", callable_mp(this, &EditorInspector::_property_pinned));
			ep->connect("selected", callable_mp(this, &EditorInspector::_property_selected));
			ep->connect("multiple_properties_changed", callable_mp(this, &EditorInspector::_multiple_properties_changed));
			ep->connect("resource_selected", callable_mp(this, &EditorInspector::_resource_selected), CONNECT_DEFERRED);
			ep->connect("object_id_selected", callable_mp(this, &EditorInspector::_object_id_selected), CONNECT_DEFERRED);
			if (F.properties.size()) {
				if (F.properties.size() == 1) {