### Godot version

4.0.3

### System information

Win7

### Issue description

#if and #else highlighted with the color same as if and else shader statement:

![image](https://github.com/godotengine/godot/assets/28286958/c2d58151-d6d2-4305-b4da-36e76e316caf)


### Steps to reproduce

1. Create shader
2. Add #if and #else

### Minimal reproduction project

N/A
bool changed = false;
	bool warnings_enabled = GLOBAL_GET("debug/shader_language/warnings/enable").booleanize();
	if (warnings_enabled != saved_warnings_enabled) {
		saved_warnings_enabled = warnings_enabled;
		changed = true;
	}
	bool treat_warning_as_errors = GLOBAL_GET("debug/shader_language/warnings/treat_warnings_as_errors").booleanize();
	if (treat_warning_as_errors != saved_treat_warning_as_errors) {
		saved_treat_warning_as_errors = treat_warning_as_errors;
		changed = true;
	}
	bool update_flags = false;
	for (int i = 0; i < ShaderWarning::WARNING_MAX; i++) {
		ShaderWarning::Code code = (ShaderWarning::Code)i;
		bool value = GLOBAL_GET("debug/shader_language/warnings/" + ShaderWarning::get_name_from_code(code).to_lower());
		if (saved_warnings[code] != value) {
			saved_warnings[code] = value;
			update_flags = true;
			changed = true;
		}
	}
	if (update_flags) {
		saved_warning_flags = (uint32_t)ShaderWarning::get_flags_from_codemap(saved_warnings);
	}
	if (p_validate && changed && shader_editor && shader_editor->get_edited_shader().is_valid()) {
		shader_editor->validate_script();
	}
}
void TextShaderEditor::_check_for_external_edit() {