### 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)

}
	}
	if (render_cubemap) {
		
		_render_shadow_append(render_fb, p_instances, light_projection, light_transform, zfar, 0, 0, false, false, use_pancake, p_camera_plane, p_lod_distance_multiplier, p_screen_mesh_lod_threshold, Rect2(), false, true, true, true, p_render_info);
		if (finalize_cubemap) {
			_render_shadow_process();
			_render_shadow_end(RD::BARRIER_MASK_FRAGMENT);
			
			Rect2 atlas_rect_norm = atlas_rect;
			atlas_rect_norm.position /= float(atlas_size);
			atlas_rect_norm.size /= float(atlas_size);
			copy_effects->copy_cubemap_to_dp(render_texture, atlas_fb, atlas_rect_norm, atlas_rect.size, light_projection.get_z_near(), light_projection.get_z_far(), false, RD::BARRIER_MASK_NO_BARRIER);
			atlas_rect_norm.position += Vector2(dual_paraboloid_offset) * atlas_rect_norm.size;
			copy_effects->copy_cubemap_to_dp(render_texture, atlas_fb, atlas_rect_norm, atlas_rect.size, light_projection.get_z_near(), light_projection.get_z_far(), true, RD::BARRIER_MASK_NO_BARRIER);
			
			light_storage->light_instance_set_shadow_transform(p_light, Projection(), light_storage->light_instance_get_base_transform(p_light), zfar, 0, 0, 0);
		}
	} else {
		
		_render_shadow_append(render_fb, p_instances, light_projection, light_transform, zfar, 0, 0, using_dual_paraboloid, using_dual_paraboloid_flip, use_pancake, p_camera_plane, p_lod_distance_multiplier, p_screen_mesh_lod_threshold, atlas_rect, flip_y, p_clear_region, p_open_pass, p_close_pass, p_render_info);
	}
}
void RenderForwardMobile::_render_shadow_begin() {
	scene_state.shadow_passes.clear();
	RD::get_singleton()->draw_command_begin_label("Shadow Setup");
	_update_render_base_uniform_set();
	render_list[RENDER_LIST_SECONDARY].clear();
}
void RenderForwardMobile::_render_shadow_append(RID p_framebuffer, const PagedArray<RenderGeometryInstance *> &p_instances, const Projection &p_projection, const Transform3D &p_transform, float p_zfar, float p_bias, float p_normal_bias, bool p_use_dp, bool p_use_dp_flip, bool p_use_pancake, const Plane &p_camera_plane, float p_lod_distance_multiplier, float p_screen_mesh_lod_threshold, const Rect2i &p_rect, bool p_flip_y, bool p_clear_region, bool p_begin, bool p_end, RenderingMethod::RenderInfo *p_render_info) {