### 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)

BakeStepUD *bsud = (BakeStepUD *)ud;
	bool ret = false;
	if (bsud->func) {
		ret = bsud->func(bsud->from_percent + p_completion * (bsud->to_percent - bsud->from_percent), p_text, bsud->ud, p_refresh);
	}
	return ret;
}
void LightmapGI::_plot_triangle_into_octree(GenProbesOctree *p_cell, float p_cell_size, const Vector3 *p_triangle) {