### Godot version

4.1.1

### System information

windows 11, mobile renderer

### Issue description

On Mobile Vulkan renderer, the clear color is 50% lighter than expected

See steps to reproduce and Minimal reproduction project below.

The box and background have the same color on Forward+ and compatibility, but not on Mobile
happens also in runtime on exported project, not only in editor preview

Images of the same scene from
compatibility:
![compatibility](https://github.com/godotengine/godot/assets/11915378/a874fa86-c16f-43ef-aed7-c2066b770ac1)
Forward+:
![forward](https://github.com/godotengine/godot/assets/11915378/e416f9a6-dfd4-4c47-bbc2-b552ca58f83c)
Mobile:
![mobile](https://github.com/godotengine/godot/assets/11915378/e28e2db8-f7c3-47e2-8c0a-44ce937c9270)


### Steps to reproduce

 - add a CSGBox3D with "unshaded" shading, and albedo of #545454
 - add environment with Background = Custom color and color of #545454

Box and background are not the same color

### Minimal reproduction project

[bg_color.zip](https://github.com/godotengine/godot/files/12174822/bg_color.zip)

return ((1 << RS::INSTANCE_LIGHT) + (1 << RS::INSTANCE_REFLECTION_PROBE) + (1 << RS::INSTANCE_DECAL));
}
void RenderForwardMobile::GeometryInstanceForwardMobile::pair_light_instances(const RID *p_light_instances, uint32_t p_light_instance_count) {
	omni_light_count = 0;
	spot_light_count = 0;
	for (uint32_t i = 0; i < p_light_instance_count; i++) {
		RS::LightType type = RendererRD::LightStorage::get_singleton()->light_instance_get_type(p_light_instances[i]);
		switch (type) {
			case RS::LIGHT_OMNI: {
				if (omni_light_count < (uint32_t)MAX_RDL_CULL) {
					omni_lights[omni_light_count] = RendererRD::LightStorage::get_singleton()->light_instance_get_forward_id(p_light_instances[i]);
					omni_light_count++;
				}
			} break;
			case RS::LIGHT_SPOT: {
				if (spot_light_count < (uint32_t)MAX_RDL_CULL) {
					spot_lights[spot_light_count] = RendererRD::LightStorage::get_singleton()->light_instance_get_forward_id(p_light_instances[i]);
					spot_light_count++;
				}
			} break;
			default:
				break;
		}
	}
}
void RenderForwardMobile::GeometryInstanceForwardMobile::pair_reflection_probe_instances(const RID *p_reflection_probe_instances, uint32_t p_reflection_probe_instance_count) {