fix(ci) fix guardian ci (#13911)

## Summary
#13910 was merged with some unused imports, let's fix this

## Testing
- [x] Let's make sure CI is green

---------

Co-authored-by: Charles Cunningham <ccunningham@openai.com>
Co-authored-by: Codex <noreply@openai.com>

codex-rs/core/src/codex_tests_guardian.rs

@@ -17,6 +17,7 @@ use codex_protocol::models::FunctionCallOutputBody;
 use codex_protocol::models::NetworkPermissions;
 use codex_protocol::models::PermissionProfile;
 use codex_utils_absolute_path::AbsolutePathBuf;
+use core_test_support::codex_linux_sandbox_exe_or_skip;
 use pretty_assertions::assert_eq;
 use serde::Deserialize;
 use std::collections::HashMap;
@@ -27,6 +28,7 @@ use tempfile::tempdir;
 #[tokio::test]
 async fn guardian_allows_shell_additional_permissions_requests_past_policy_validation() {
     let (mut session, mut turn_context_raw) = make_session_and_context().await;
+    turn_context_raw.codex_linux_sandbox_exe = codex_linux_sandbox_exe_or_skip!();
     turn_context_raw
         .approval_policy
         .set(AskForApproval::OnRequest)