### Godot version

4.1.1

### System information

linux

### Issue description

- When favoriting a path in a `FileDialog`, clicking on it travels to `path/to/dir/`.
- When going up a level from there, it doesn't go to `path/to` but to `path/to/dir` (without the `/`).

[simplescreenrecorder-2023-08-18_09.38.37.webm](https://github.com/godotengine/godot/assets/71937306/00c20ad3-292f-4961-84ed-dbc64906df52)

The problem is either (or both) that:
 - loaded path has a trailing `/`
 - parent dir of `stuff/` is considered to be `stuff`

### Steps to reproduce

favorite a directory and use the feature to navigate to it

### Minimal reproduction project

any (i.e. the project manager's "new project" dialog has one)
if (local_history_pos >= local_history.size() - 1) {
		return;
	}
	local_history_pos++;
	dir_access->change_dir(local_history[local_history_pos]);
	update_file_list();
	update_dir();
	dir_prev->set_disabled(local_history_pos == 0);
	dir_next->set_disabled(local_history_pos == local_history.size() - 1);
}
bool EditorFileDialog::default_show_hidden_files = false;
EditorFileDialog::DisplayMode EditorFileDialog::default_display_mode = DISPLAY_THUMBNAILS;
void EditorFileDialog::set_display_mode(DisplayMode p_mode) {
	if (display_mode == p_mode) {
		return;
	}
	if (p_mode == DISPLAY_THUMBNAILS) {
		mode_list->set_pressed(false);
		mode_thumbnails->set_pressed(true);
	} else {
		mode_thumbnails->set_pressed(false);
		mode_list->set_pressed(true);
	}
	display_mode = p_mode;
	invalidate();
}
EditorFileDialog::DisplayMode EditorFileDialog::get_display_mode() const {
	return display_mode;
}
void EditorFileDialog::_bind_methods() {