### Godot version

4.0.beta10.official [d0398f62f]

### System information

Windows 10, Vulkan, NVIDIA GeForce RTX 2060m (31.0.15.2698)

### Issue description

I'm getting some kind of clustering/blocky artifact when using spotlights, with no fog or any fancy rendering stuff whatsoever.
I've looked through a bunch of similar issues, but the only ones I could find were related to volumetric fog or other environment effects that I am not using.
Not sure if I'm just missing something, but I think I've played with every option in the spotlight and every option in a WorldEnvironment and nothing makes it go away.

The only lead I have is that the intensity of the artifact seems to be affected by the spot angle. It cycles in a sawtooth pattern every ~0.07 degrees.

![image](https://user-images.githubusercontent.com/13819558/209914720-77a637ea-8cc7-4cff-8216-363f9150885a.png)

Lmk if you need more info or need me to try anything.

### Steps to reproduce

1. New Project (Forward+)
2. Put down some MeshInstance3Ds as a backdrop
3. Put a SpotLight3D
4. Raise spotlight intensity, lower spot angle, and increase range to see it better
5. Slowly increase spot angle to see cycling effect

### Minimal reproduction project

[testspotlight.zip](https://github.com/godotengine/godot/files/10318069/testspotlight.zip)

if (!is_inside_tree()) {
		return;
	}
	bool editor_ok = true;
#ifdef TOOLS_ENABLED
	if (editor_only) {
		if (!Engine::get_singleton()->is_editor_hint()) {
			editor_ok = false;
		} else {
			editor_ok = (get_tree()->get_edited_scene_root() && (this == get_tree()->get_edited_scene_root() || get_owner() == get_tree()->get_edited_scene_root()));
		}
	}
#else
	if (editor_only) {
		editor_ok = false;
	}
#endif
	RS::get_singleton()->instance_set_visible(get_instance(), is_visible_in_tree() && editor_ok);
}
void Light3D::_notification(int p_what) {
	switch (p_what) {
		case NOTIFICATION_VISIBILITY_CHANGED:
		case NOTIFICATION_ENTER_TREE: {
			_update_visibility();
		} break;
	}
}
void Light3D::set_editor_only(bool p_editor_only) {