### 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)

}
		uniforms.push_back(u);
	}
	
	{
		RD::Uniform u;
		u.binding = 6;
		u.uniform_type = RD::UNIFORM_TYPE_TEXTURE;
		RID default_tex = texture_storage->texture_rd_get_default(RendererRD::TextureStorage::DEFAULT_RD_TEXTURE_2D_ARRAY_WHITE);
		for (uint32_t i = 0; i < scene_state.max_lightmaps; i++) {
			if (p_render_data && i < p_render_data->lightmaps->size()) {
				RID base = light_storage->lightmap_instance_get_lightmap((*p_render_data->lightmaps)[i]);
				RID texture = light_storage->lightmap_get_texture(base);
				RID rd_texture = texture_storage->texture_get_rd_texture(texture);
				u.append_id(rd_texture);
			} else {
				u.append_id(default_tex);
			}
		}
		uniforms.push_back(u);
	}
	/*
	{
		RD::Uniform u;
		u.binding = 7;
		u.uniform_type = RD::UNIFORM_TYPE_TEXTURE;
		u.ids.resize(MAX_VOXEL_GI_INSTANCESS);
		RID default_tex = texture_storage->texture_rd_get_default(RendererRD::TextureStorage::DEFAULT_RD_TEXTURE_3D_WHITE);
		for (int i = 0; i < MAX_VOXEL_GI_INSTANCESS; i++) {
			if (i < (int)p_voxel_gi_instances.size()) {