Pause Tokio time in the reused Guardian session test (#56007)

Pause the Tokio clock before spawning the review in
`run_review_on_reused_session_waits_for_submitted_turn` so its one-second
deadline uses simulated time while the test verifies that stale turn completions
are ignored.

GitOrigin-RevId: c6712219f894835b576f499eb080ec15a3f09a78

codex-rs/core/src/guardian/review_session_tests.rs

@@ -720,6 +720,8 @@ async fn run_review_on_reused_session_waits_for_submitted_turn() {
     }
     let params = test_review_params().await;
 
+    tokio::time::pause();
+
     let review = tokio::spawn(async move {
         run_review_on_session(
             &review_session,