gh-93297: Make asyncio task groups prevent child tasks from being GCed (GH-93299) (#93305)

(cherry picked from commit e6a57678cafe18ca132ee9510252168fcc392a8d)

Co-authored-by: Yury Selivanov <yury@edgedb.com>

Co-authored-by: Yury Selivanov <yury@edgedb.com>
2 files changed