### 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)

return blend_splits;
}
void DirectionalLight3D::set_sky_mode(SkyMode p_mode) {
	sky_mode = p_mode;
	RS::get_singleton()->light_directional_set_sky_mode(light, RS::LightDirectionalSkyMode(p_mode));
}
DirectionalLight3D::SkyMode DirectionalLight3D::get_sky_mode() const {
	return sky_mode;
}
void DirectionalLight3D::_validate_property(PropertyInfo &p_property) const {
	if (shadow_mode == SHADOW_ORTHOGONAL && (p_property.name == "directional_shadow_split_1" || p_property.name == "directional_shadow_blend_splits")) {
		
		p_property.usage = PROPERTY_USAGE_NO_EDITOR;
	}
	if ((shadow_mode == SHADOW_ORTHOGONAL || shadow_mode == SHADOW_PARALLEL_2_SPLITS) && (p_property.name == "directional_shadow_split_2" || p_property.name == "directional_shadow_split_3")) {
		
		p_property.usage = PROPERTY_USAGE_NO_EDITOR;
	}
	if (p_property.name == "light_size" || p_property.name == "light_projector" || p_property.name == "light_specular") {
		
		p_property.usage = PROPERTY_USAGE_NONE;
	}
	if (p_property.name == "distance_fade_enabled" || p_property.name == "distance_fade_begin" || p_property.name == "distance_fade_shadow" || p_property.name == "distance_fade_length") {
		
		
		p_property.usage = PROPERTY_USAGE_NONE;
	}
}
void DirectionalLight3D::_bind_methods() {