### Godot version

4.0 beta 17

### System information

Windows 11, Forward+, RTX 4090

### Issue description

In the latest beta, baking LightmapGI has taken a big performance hit. The baking itself might not be the problem, it's the (Re)Importing Assets step for the `.exr` that seems to take all the time.




### Steps to reproduce

I've included a repro project to demonstrate it. Click the `LightmapGI` node and then the `Bake Lightmaps` button.

Before Beta 17:
`Done baking lightmaps in 00:00:01.`

With Beta 17 (and the latest Master branch, just in case):
`Done baking lightmaps in 00:00:08.`



### Minimal reproduction project

[lightmap-regression-repro.zip](https://github.com/godotengine/godot/files/10579835/lightmap-regression-repro.zip)

}
	}
	float exposure_normalization = 1.0;
	if (camera_attributes.is_valid()) {
		exposure_normalization = camera_attributes->get_exposure_multiplier();
		if (GLOBAL_GET("rendering/lights_and_shadows/use_physical_light_units")) {
			exposure_normalization = camera_attributes->calculate_exposure_normalization();
		}
	}
	Lightmapper::BakeError bake_err = lightmapper->bake(Lightmapper::BakeQuality(bake_quality), use_denoiser, bounces, bias, max_texture_size, directional, Lightmapper::GenerateProbes(gen_probes), environment_image, environment_transform, _lightmap_bake_step_function, &bsud, exposure_normalization);
	if (bake_err == Lightmapper::BAKE_ERROR_LIGHTMAP_CANT_PRE_BAKE_MESHES) {
		return BAKE_ERROR_MESHES_INVALID;
	}
	
	Ref<LightmapGIData> gi_data;
	if (get_light_data().is_valid()) {
		gi_data = get_light_data();
		set_light_data(Ref<LightmapGIData>()); 
		gi_data->clear();
	} else {
		gi_data.instantiate();
	}
	Ref<Texture2DArray> texture;
	{
		Vector<Ref<Image>> images;
		for (int i = 0; i < lightmapper->get_bake_texture_count(); i++) {
			images.push_back(lightmapper->get_bake_texture(i));
		}
		texture.instantiate();
		texture->create_from_images(images);