### 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
glBlendFuncSeparate(GL_SRC_ALPHA, GL_ONE_MINUS_SRC_ALPHA, GL_ZERO, GL_ONE);
							}
						} break;
						case GLES3::SceneShaderData::BLEND_MODE_ADD: {
							glBlendEquation(GL_FUNC_ADD);
							glBlendFunc(p_pass_mode == PASS_MODE_COLOR_TRANSPARENT ? GL_SRC_ALPHA : GL_ONE, GL_ONE);
						} break;
						case GLES3::SceneShaderData::BLEND_MODE_SUB: {
							glBlendEquation(GL_FUNC_REVERSE_SUBTRACT);
							glBlendFunc(GL_SRC_ALPHA, GL_ONE);
						} break;
						case GLES3::SceneShaderData::BLEND_MODE_MUL: {
							glBlendEquation(GL_FUNC_ADD);
							if (p_render_data->transparent_bg) {
								glBlendFuncSeparate(GL_DST_COLOR, GL_ZERO, GL_DST_ALPHA, GL_ZERO);
							} else {
								glBlendFuncSeparate(GL_DST_COLOR, GL_ZERO, GL_ZERO, GL_ONE);
							}
						} break;
						case GLES3::SceneShaderData::BLEND_MODE_ALPHA_TO_COVERAGE: {
							
						} break;
					}
					scene_state.current_blend_mode = desired_blend_mode;
				}
			}
			
			GLES3::SceneShaderData::Cull cull_mode = shader->cull_mode;
			if ((surf->flags & GeometryInstanceSurface::FLAG_USES_DOUBLE_SIDED_SHADOWS)) {
				cull_mode = GLES3::SceneShaderData::CULL_DISABLED;