### 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("get_environment_custom_sky"), &LightmapGI::get_environment_custom_sky);
	ClassDB::bind_method(D_METHOD("set_environment_custom_color", "color"), &LightmapGI::set_environment_custom_color);
	ClassDB::bind_method(D_METHOD("get_environment_custom_color"), &LightmapGI::get_environment_custom_color);
	ClassDB::bind_method(D_METHOD("set_environment_custom_energy", "energy"), &LightmapGI::set_environment_custom_energy);
	ClassDB::bind_method(D_METHOD("get_environment_custom_energy"), &LightmapGI::get_environment_custom_energy);
	ClassDB::bind_method(D_METHOD("set_max_texture_size", "max_texture_size"), &LightmapGI::set_max_texture_size);
	ClassDB::bind_method(D_METHOD("get_max_texture_size"), &LightmapGI::get_max_texture_size);
	ClassDB::bind_method(D_METHOD("set_use_denoiser", "use_denoiser"), &LightmapGI::set_use_denoiser);
	ClassDB::bind_method(D_METHOD("is_using_denoiser"), &LightmapGI::is_using_denoiser);
	ClassDB::bind_method(D_METHOD("set_interior", "enable"), &LightmapGI::set_interior);
	ClassDB::bind_method(D_METHOD("is_interior"), &LightmapGI::is_interior);
	ClassDB::bind_method(D_METHOD("set_directional", "directional"), &LightmapGI::set_directional);
	ClassDB::bind_method(D_METHOD("is_directional"), &LightmapGI::is_directional);
	ClassDB::bind_method(D_METHOD("set_camera_attributes", "camera_attributes"), &LightmapGI::set_camera_attributes);
	ClassDB::bind_method(D_METHOD("get_camera_attributes"), &LightmapGI::get_camera_attributes);
	
	ADD_GROUP("Tweaks", "");
	ADD_PROPERTY(PropertyInfo(Variant::INT, "quality", PROPERTY_HINT_ENUM, "Low,Medium,High,Ultra"), "set_bake_quality", "get_bake_quality");
	ADD_PROPERTY(PropertyInfo(Variant::INT, "bounces", PROPERTY_HINT_RANGE, "0,16,1"), "set_bounces", "get_bounces");
	ADD_PROPERTY(PropertyInfo(Variant::BOOL, "directional"), "set_directional", "is_directional");
	ADD_PROPERTY(PropertyInfo(Variant::BOOL, "interior"), "set_interior", "is_interior");
	ADD_PROPERTY(PropertyInfo(Variant::BOOL, "use_denoiser"), "set_use_denoiser", "is_using_denoiser");
	ADD_PROPERTY(PropertyInfo(Variant::FLOAT, "bias", PROPERTY_HINT_RANGE, "0.00001,0.1,0.00001,or_greater"), "set_bias", "get_bias");
	ADD_PROPERTY(PropertyInfo(Variant::INT, "max_texture_size", PROPERTY_HINT_RANGE, "2048,16384,1"), "set_max_texture_size", "get_max_texture_size");
	ADD_GROUP("Environment", "environment_");
	ADD_PROPERTY(PropertyInfo(Variant::INT, "environment_mode", PROPERTY_HINT_ENUM, "Disabled,Scene,Custom Sky,Custom Color"), "set_environment_mode", "get_environment_mode");
	ADD_PROPERTY(PropertyInfo(Variant::OBJECT, "environment_custom_sky", PROPERTY_HINT_RESOURCE_TYPE, "Sky"), "set_environment_custom_sky", "get_environment_custom_sky");
	ADD_PROPERTY(PropertyInfo(Variant::COLOR, "environment_custom_color", PROPERTY_HINT_COLOR_NO_ALPHA), "set_environment_custom_color", "get_environment_custom_color");
	ADD_PROPERTY(PropertyInfo(Variant::FLOAT, "environment_custom_energy", PROPERTY_HINT_RANGE, "0,64,0.01"), "set_environment_custom_energy", "get_environment_custom_energy");
	ADD_PROPERTY(PropertyInfo(Variant::OBJECT, "camera_attributes", PROPERTY_HINT_RESOURCE_TYPE, "CameraAttributesPractical,CameraAttributesPhysical"), "set_camera_attributes", "get_camera_attributes");