### 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)
filters.clear();
	update_filters();
	invalidate();
}
void EditorFileDialog::add_filter(const String &p_filter, const String &p_description) {
	if (p_description.is_empty()) {
		filters.push_back(p_filter);
	} else {
		filters.push_back(vformat("%s ; %s", p_filter, p_description));
	}
	update_filters();
	invalidate();
}
void EditorFileDialog::set_filters(const Vector<String> &p_filters) {
	if (filters == p_filters) {
		return;
	}
	filters = p_filters;
	update_filters();
	invalidate();
}
Vector<String> EditorFileDialog::get_filters() const {