### Godot version

v4.0.beta.custom_build [fab9926a9]

### System information

Fedora 37

### Issue description

When creating a new inherited scene, saving the scene (for example with Ctrl+S) defaults to overwriting the scene being inherited, instead of prompting for a location to save to.

### Steps to reproduce

1. Create a new inherited scene
2. Press Ctrl+S

If the scene being inherited is imported (for example from a glTF), an error displays. If the inherited scene is a .tscn or .scn, it gets overridden by an inherited scene that tries to inherit itself, which is impossible and thus corrupt.

### Minimal reproduction project

N/A
ERR_FAIL_COND_MSG(p_full_paths.size() != r_filenames.size(), vformat("disambiguate_filenames requires two string vectors of same length (%d != %d).", p_full_paths.size(), r_filenames.size()));
	
	
	Vector<RBSet<int>> index_sets;
	HashMap<String, int> scene_name_to_set_index;
	for (int i = 0; i < r_filenames.size(); i++) {
		String scene_name = r_filenames[i];
		if (!scene_name_to_set_index.has(scene_name)) {
			index_sets.append(RBSet<int>());
			scene_name_to_set_index.insert(r_filenames[i], index_sets.size() - 1);
		}