### Godot version

v4.1.stable.official [970459615]  < Steam

### System information

Godot v4.1.stable - Debian GNU/Linux trixie/sid trixie - Vulkan (Mobile) - dedicated NVIDIA GeForce GTX 1060 (nvidia) - Intel(R) Core(TM) i5-8400 CPU @ 2.80GHz (6 Threads)

### Issue description

After being upgraded to 4.1 via Steam (before any release announcement even! The speed!), I saw the warning marker against my game in the project manager, and noticed that the tooltip wasn't all that helpful:

![Screenshot_20230706_121443](https://github.com/godotengine/godot/assets/441188/7e62f67c-664f-4f5f-8f84-0cd0084679a6)

It seems to think that the old version number is a deprecated feature? :/

### Steps to reproduce

1. Have a project from Godot 4.0
2. Upgrade Godot to 4.1
3. Open project manager

Alternatively:
1. Create a new project in 4.1
2. Quit Godot
3. Edit the `project.godot`'s `config/features` to read `4.0` instead of `4.1`
4. Open project manager

### Minimal reproduction project

[default.zip](https://github.com/godotengine/godot/files/11967512/default.zip)

if (p_path.get_extension().to_lower() == "godot") {
		return singleton->icon_type_cache["GodotMonochrome"];
	}
	return singleton->icon_type_cache["Object"];
}
Ref<Texture2D> ProjectManager::_file_dialog_get_thumbnail(const String &p_path) {
	if (p_path.get_extension().to_lower() == "godot") {
		return singleton->icon_type_cache["GodotFile"];
	}
	return Ref<Texture2D>();
}
void ProjectManager::_build_icon_type_cache(Ref<Theme> p_theme) {
	if (p_theme.is_null()) {
		return;
	}
	List<StringName> tl;
	p_theme->get_icon_list(SNAME("EdorIcons"), &tl);
	for (List<StringName>::Element *E = tl.front(); E; E = E->next()) {
		icon_type_cache[E->get()] = p_theme->get_icon(E->get(), SNAME("EdorIcons"));
	}
}
void ProjectManager::_dim_window() {