[3.10] gh-94949: Disallow parsing parenthesised ctx mgr with old feature_version (GH-94950) (#94990)

(cherry picked from commit 0daba822212cd5d6c63384a27f390f0945330c2b)

Co-authored-by: Shantanu <12621235+hauntsaninja@users.noreply.github.com>