### Godot version

v4.0.stable.official [92bee43ad]

### System information

Linux - v4.0.stable.official [92bee43ad]

### Issue description

It gives you the possibility of removing unexisting key/value pairs from a dictionary.

### Steps to reproduce

![image](https://github.com/godotengine/godot/assets/69520693/35beadbe-bfdd-4176-9b26-222bbf69cafa)
![image](https://github.com/godotengine/godot/assets/69520693/7ed647e0-a2af-4e58-9f00-f77b7bc7bb02)
![image](https://github.com/godotengine/godot/assets/69520693/f08bf824-8408-45eb-bb84-f1dc7e19e392)


### Minimal reproduction project

N/A
String name = p_name;
	if (name == "new_item_key") {
		r_ret = new_item_key;
		return true;
	}
	if (name == "new_item_value") {
		r_ret = new_item_value;
		return true;
	}
	if (name.begins_with("indices")) {
		int index = name.get_slicec('/', 1).to_int();
		Variant key = dict.get_key_at_index(index);
		r_ret = dict[key];
		if (r_ret.get_type() == Variant::OBJECT && Object::cast_to<EncodedObjectAsID>(r_ret)) {
			r_ret = Object::cast_to<EncodedObjectAsID>(r_ret)->get_object_id();
		}
		return true;
	}
	return false;
}
void EditorPropertyDictionaryObject::set_dict(const Dictionary &p_dict) {
	dict = p_dict;
}
Dictionary EditorPropertyDictionaryObject::get_dict() {
	return dict;
}
void EditorPropertyDictionaryObject::set_new_item_key(const Variant &p_new_item) {