### Godot version

4.2.dev 5ee983188de97ae027f9b9c1443438063f708a7e

### System information

Windows 10 - Compatibility renderer 

### Issue description

When running a VR project sky contribution is not working in the compatibility renderer:

![image](https://github.com/godotengine/godot/assets/1945449/7aa19569-95c8-41a2-913b-37b81f4728a7)

It is working fine in normal mode. Can be worked around by setting sky contribution to 0 and providing an ambient color.

### Steps to reproduce

Try any project with a proper sky setup in XR, just switch to compatibility renderer.

### Minimal reproduction project

I'll try and create an MVP soon that can be used without XR hardware, but for now this can be used:
https://github.com/BastiaanOlij/godot_openxr_demo
Sky *sky = sky_owner.get_or_null(p_sky);
	ERR_FAIL_NULL(sky);
	if (sky->mode == p_mode) {
		return;
	}
	sky->mode = p_mode;
	_invalidate_sky(sky);
}
void RasterizerSceneGLES3::sky_set_material(RID p_sky, RID p_material) {
	Sky *sky = sky_owner.get_or_null(p_sky);
	ERR_FAIL_NULL(sky);
	if (sky->material == p_material) {
		return;
	}
	sky->material = p_material;
	_invalidate_sky(sky);
}
float RasterizerSceneGLES3::sky_get_baked_exposure(RID p_sky) const {
	Sky *sky = sky_owner.get_or_null(p_sky);
	ERR_FAIL_NULL_V(sky, 1.0);
	return sky->baked_exposure;
}
void RasterizerSceneGLES3::_invalidate_sky(Sky *p_sky) {
	if (!p_sky->dirty) {
		p_sky->dirty = true;
		p_sky->dirty_list = dirty_sky_list;
		dirty_sky_list = p_sky;
	}
}
void RasterizerSceneGLES3::_update_dirty_skys() {