Async TLS: Ensure wrapped transport is closed once

[francis-clairicia]

No description provided.

[codecov]

Codecov Report

All modified and coverable lines are covered by tests ✅

Project coverage is 100.00%. Comparing base (f5667d5) to head (c6b8f15).
Report is 58 commits behind head on main.

Additional details and impacted files

Flag	Coverage Δ
OS-Linux	99.90% <100.00%> (+<0.01%)	⬆️
OS-Windows	99.78% <100.00%> (+<0.01%)	⬆️
OS-macOS	99.90% <100.00%> (+<0.01%)	⬆️
Py-3.11	99.90% <100.00%> (+<0.01%)	⬆️
Py-3.12	99.94% <100.00%> (+<0.01%)	⬆️
test-functional	81.82% <100.00%> (+0.01%)	⬆️
test-unit	89.76% <100.00%> (+<0.01%)	⬆️

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