### 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)

lightmap = RS::get_singleton()->lightmap_create();
}
LightmapGIData::~LightmapGIData() {
	ERR_FAIL_NULL(RenderingServer::get_singleton());
	RS::get_singleton()->free(lightmap);
}
void LightmapGI::_find_meshes_and_lights(Node *p_at_node, Vector<MeshesFound> &meshes, Vector<LightsFound> &lights, Vector<Vector3> &probes) {
	MeshInstance3D *mi = Object::cast_to<MeshInstance3D>(p_at_node);
	if (mi && mi->get_gi_mode() == GeometryInstance3D::GI_MODE_STATIC && mi->is_visible_in_tree()) {
		Ref<Mesh> mesh = mi->get_mesh();
		if (mesh.is_valid()) {
			bool all_have_uv2_and_normal = true;
			bool surfaces_found = false;
			for (int i = 0; i < mesh->get_surface_count(); i++) {
				if (mesh->surface_get_primitive_type(i) != Mesh::PRIMITIVE_TRIANGLES) {
					continue;
				}
				if (!(mesh->surface_get_format(i) & Mesh::ARRAY_FORMAT_TEX_UV2)) {
					all_have_uv2_and_normal = false;
					break;
				}
				if (!(mesh->surface_get_format(i) & Mesh::ARRAY_FORMAT_NORMAL)) {
					all_have_uv2_and_normal = false;
					break;
				}
				surfaces_found = true;
			}
			if (surfaces_found && all_have_uv2_and_normal) {
				
				MeshesFound mf;