[3.7] bpo-37658: Fix asyncio.wait_for() to respect waited task status (GH-21894) by elprans · Pull Request #21969 · python/cpython

…pythonGH-21894)

Currently, if `asyncio.wait_for()` itself is cancelled it will always
raise `CancelledError` regardless if the underlying task is still
running.  This is similar to a race with the timeout, which is handled
already..
(cherry picked from commit a2118a1)

Co-authored-by: Elvis Pranskevichus <elvis@magic.io>