### 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)

#include "lightmap_gi.h"
#include "core/config/project_settings.h"
#include "core/io/config_file.h"
#include "core/math/delaunay_3d.h"
#include "lightmap_probe.h"
#include "scene/3d/mesh_instance_3d.h"
#include "scene/resources/camera_attributes.h"
#include "scene/resources/environment.h"
#include "scene/resources/sky.h"
void LightmapGIData::add_user(const NodePath &p_path, const Rect2 &p_uv_scale, int p_slice_index, int32_t p_sub_instance) {
	User user;
	user.path = p_path;
	user.uv_scale = p_uv_scale;
	user.slice_index = p_slice_index;
	user.sub_instance = p_sub_instance;
	users.push_back(user);
}
int LightmapGIData::get_user_count() const {