### Godot version

4.0 Stable

### System information

Ubuntu 22.04

### Issue description

Setting fog_affect_sky = 1 do not have the desired effect when using a Color sky mode. It works properly if we use a procedural sky or the forward+ renderer.

![Screenshot from 2023-03-03 16-50-53](https://user-images.githubusercontent.com/8985409/222870514-0195c4cb-bbca-4e9b-bb6a-6e2a568d2f7b.png)


### Steps to reproduce

Add a sky with a plain color mode like the Clear Color default option. Enable fog and set fog_affect_sky value to 1. Sky is still not affected by fog. 

### Minimal reproduction project
[mobile_fog_sky_bug.zip](https://github.com/godotengine/godot/files/10887265/mobile_fog_sky_bug.zip)


if (use_msaa) {
				
				pass.resolve_attachments.push_back(color_buffer_id);
			}
			passes.push_back(pass);
			return FramebufferCacheRD::get_singleton()->get_cache_multipass(textures, passes, view_count);
		} break;
		case FB_CONFIG_THREE_SUBPASSES: {
			
			passes.push_back(pass);
			
			passes.push_back(pass);
			
			if (use_msaa) {
				
				pass.resolve_attachments.push_back(color_buffer_id);
			}
			passes.push_back(pass);
			return FramebufferCacheRD::get_singleton()->get_cache_multipass(textures, passes, view_count);
		} break;
		case FB_CONFIG_FOUR_SUBPASSES: {
			Size2i target_size = render_buffers->get_target_size();
			Size2i internal_size = render_buffers->get_internal_size();
			
			ERR_FAIL_COND_V(target_size != internal_size, RID());
			
			passes.push_back(pass);
			
			passes.push_back(pass);