### 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)

ClassDB::bind_method(D_METHOD("_set_user_data", "data"), &LightmapGIData::_set_user_data);
	ClassDB::bind_method(D_METHOD("_get_user_data"), &LightmapGIData::_get_user_data);
	ClassDB::bind_method(D_METHOD("set_light_texture", "light_texture"), &LightmapGIData::set_light_texture);
	ClassDB::bind_method(D_METHOD("get_light_texture"), &LightmapGIData::get_light_texture);
	ClassDB::bind_method(D_METHOD("_set_light_textures_data", "data"), &LightmapGIData::_set_light_textures_data);
	ClassDB::bind_method(D_METHOD("_get_light_textures_data"), &LightmapGIData::_get_light_textures_data);
	ClassDB::bind_method(D_METHOD("set_uses_spherical_harmonics", "uses_spherical_harmonics"), &LightmapGIData::set_uses_spherical_harmonics);
	ClassDB::bind_method(D_METHOD("is_using_spherical_harmonics"), &LightmapGIData::is_using_spherical_harmonics);
	ClassDB::bind_method(D_METHOD("add_user", "path", "uv_scale", "slice_index", "sub_instance"), &LightmapGIData::add_user);
	ClassDB::bind_method(D_METHOD("get_user_count"), &LightmapGIData::get_user_count);
	ClassDB::bind_method(D_METHOD("get_user_path", "user_idx"), &LightmapGIData::get_user_path);
	ClassDB::bind_method(D_METHOD("clear_users"), &LightmapGIData::clear_users);
	ClassDB::bind_method(D_METHOD("_set_probe_data", "data"), &LightmapGIData::_set_probe_data);
	ClassDB::bind_method(D_METHOD("_get_probe_data"), &LightmapGIData::_get_probe_data);
	ADD_PROPERTY(PropertyInfo(Variant::OBJECT, "light_texture", PROPERTY_HINT_RESOURCE_TYPE, "TextureLayered", PROPERTY_USAGE_EDITOR), "set_light_texture", "get_light_texture"); 
	ADD_PROPERTY(PropertyInfo(Variant::ARRAY, "light_textures", PROPERTY_HINT_NONE, "", PROPERTY_USAGE_NO_EDITOR | PROPERTY_USAGE_INTERNAL), "_set_light_textures_data", "_get_light_textures_data");
	ADD_PROPERTY(PropertyInfo(Variant::BOOL, "uses_spherical_harmonics", PROPERTY_HINT_NONE, "", PROPERTY_USAGE_NO_EDITOR | PROPERTY_USAGE_INTERNAL), "set_uses_spherical_harmonics", "is_using_spherical_harmonics");
	ADD_PROPERTY(PropertyInfo(Variant::ARRAY, "user_data", PROPERTY_HINT_NONE, "", PROPERTY_USAGE_NO_EDITOR | PROPERTY_USAGE_INTERNAL), "_set_user_data", "_get_user_data");
	ADD_PROPERTY(PropertyInfo(Variant::DICTIONARY, "probe_data", PROPERTY_HINT_NONE, "", PROPERTY_USAGE_NO_EDITOR | PROPERTY_USAGE_INTERNAL), "_set_probe_data", "_get_probe_data");
}
LightmapGIData::LightmapGIData() {