### 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)

temperature = p_temperature;
	if (!GLOBAL_GET("rendering/lights_and_shadows/use_physical_light_units")) {
		return;
	}
	correlated_color = _color_from_temperature(temperature);
	Color combined = color.srgb_to_linear() * correlated_color.srgb_to_linear();
	RS::get_singleton()->light_set_color(light, combined.linear_to_srgb());
	
	update_gizmos();
}
Color Light3D::get_correlated_color() const {
	return correlated_color;
}
float Light3D::get_temperature() const {
	return temperature;
}
void Light3D::_update_visibility() {