[3.13] gh-121621: Disable asyncio freelist in free-threaded build (GH-122046) (#122048)

The futureobj freelist isn't thread-safe. We intend to re-enable the
freelist in a thread-safe way for 3.14 (but not 3.13).
(cherry picked from commit 97248204a1cc10bd3a66ce857535d133f6bc86a1)