### 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
clear_color.r *= bg_energy_multiplier;
				clear_color.g *= bg_energy_multiplier;
				clear_color.b *= bg_energy_multiplier;
				if (environment_get_fog_enabled(render_data.environment)) {
					draw_sky_fog_only = true;
					GLES3::MaterialStorage::get_singleton()->material_set_param(sky_globals.fog_material, "clear_color", Variant(clear_color));
				}
			} break;
			case RS::ENV_BG_COLOR: {
				clear_color = environment_get_bg_color(render_data.environment);
				clear_color.r *= bg_energy_multiplier;
				clear_color.g *= bg_energy_multiplier;
				clear_color.b *= bg_energy_multiplier;
				if (environment_get_fog_enabled(render_data.environment)) {
					draw_sky_fog_only = true;
					GLES3::MaterialStorage::get_singleton()->material_set_param(sky_globals.fog_material, "clear_color", Variant(clear_color));
				}
			} break;
			case RS::ENV_BG_SKY: {
				draw_sky = true;
			} break;
			case RS::ENV_BG_CANVAS: {
				keep_color = true;
			} break;
			case RS::ENV_BG_KEEP: {
				keep_color = true;
			} break;
			case RS::ENV_BG_CAMERA_FEED: {
			} break;
			default: {