### 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 shadow;
}
void Light3D::set_negative(bool p_enable) {
	negative = p_enable;
	RS::get_singleton()->light_set_negative(light, p_enable);
}
bool Light3D::is_negative() const {
	return negative;
}
void Light3D::set_enable_distance_fade(bool p_enable) {
	distance_fade_enabled = p_enable;
	RS::get_singleton()->light_set_distance_fade(light, distance_fade_enabled, distance_fade_begin, distance_fade_shadow, distance_fade_length);
	notify_property_list_changed();
}
bool Light3D::is_distance_fade_enabled() const {
	return distance_fade_enabled;
}
void Light3D::set_distance_fade_begin(real_t p_distance) {
	distance_fade_begin = p_distance;
	RS::get_singleton()->light_set_distance_fade(light, distance_fade_enabled, distance_fade_begin, distance_fade_shadow, distance_fade_length);
}
real_t Light3D::get_distance_fade_begin() const {
	return distance_fade_begin;
}
void Light3D::set_distance_fade_shadow(real_t p_distance) {
	distance_fade_shadow = p_distance;
	RS::get_singleton()->light_set_distance_fade(light, distance_fade_enabled, distance_fade_begin, distance_fade_shadow, distance_fade_length);
}
real_t Light3D::get_distance_fade_shadow() const {