Task was destroyed but it's pending #4408
Description
On master, I see outputs from run_app() like follows:
======== Running on http://0.0.0.0:8080 ========
(Press CTRL+C to quit)
Task was destroyed but it is pending!
task: <Task pending name='Task-4' coro=<RequestHandler.start() done, defined at /home/andrew/.virtualenvs/multidict/lib/python3.8/site-packages/aiohttp/web_protocol.py:437> wait_for=<Future pending cb=[<TaskWakeupMethWrapper object at 0x7f8822ffef10>()]>>
I suspect it happens on errors and keepalive closing in web_protocol.py.
The message should go.