The new test_sock_client_racing() test seems to have... a race condition...

AMD64 FreeBSD Non-Debug 3.9:
https://buildbot.python.org/all/#/builders/750/builds/11

ERROR: test_sock_client_racing (test.test_asyncio.test_sock_lowlevel.KqueueEventLoopTests)
ERROR: test_sock_client_racing (test.test_asyncio.test_sock_lowlevel.PollEventLoopTests)
ERROR: test_sock_client_racing (test.test_asyncio.test_sock_lowlevel.SelectEventLoopTests)

Example:

ERROR: test_sock_client_racing (test.test_asyncio.test_sock_lowlevel.PollEventLoopTests)
----------------------------------------------------------------------
Traceback (most recent call last):
  File "/usr/home/buildbot/python/3.9.koobs-freebsd-9e36.nondebug/build/Lib/test/test_asyncio/test_sock_lowlevel.py", line 216, in _basetest_sock_connect_racing
    await self.loop.sock_connect(sock, addr)
  File "/usr/home/buildbot/python/3.9.koobs-freebsd-9e36.nondebug/build/Lib/asyncio/selector_events.py", line 500, in sock_connect
    return await fut
  File "/usr/home/buildbot/python/3.9.koobs-freebsd-9e36.nondebug/build/Lib/asyncio/selector_events.py", line 505, in _sock_connect
    sock.connect(address)
ConnectionRefusedError: [Errno 61] Connection refused

During handling of the above exception, another exception occurred:

Traceback (most recent call last):
  File "/usr/home/buildbot/python/3.9.koobs-freebsd-9e36.nondebug/build/Lib/test/test_asyncio/test_sock_lowlevel.py", line 253, in test_sock_client_racing
    self.loop.run_until_complete(asyncio.wait_for(
  File "/usr/home/buildbot/python/3.9.koobs-freebsd-9e36.nondebug/build/Lib/asyncio/base_events.py", line 642, in run_until_complete
    return future.result()
  File "/usr/home/buildbot/python/3.9.koobs-freebsd-9e36.nondebug/build/Lib/asyncio/tasks.py", line 496, in wait_for
    return fut.result()
  File "/usr/home/buildbot/python/3.9.koobs-freebsd-9e36.nondebug/build/Lib/test/test_asyncio/test_sock_lowlevel.py", line 219, in _basetest_sock_connect_racing
    await self.loop.sock_connect(sock, addr)
  File "/usr/home/buildbot/python/3.9.koobs-freebsd-9e36.nondebug/build/Lib/asyncio/selector_events.py", line 500, in sock_connect
    return await fut
  File "/usr/home/buildbot/python/3.9.koobs-freebsd-9e36.nondebug/build/Lib/asyncio/selector_events.py", line 505, in _sock_connect
    sock.connect(address)
ConnectionRefusedError: [Errno 61] Connection refused