Application doesn't exit after closing the main window with Qt 5.15.0

[Systemcluster]

With PySide2 5.15.0, the application doesn't exit after closing the main window and keeps running until the process is killed.

Log output running the aiohttp_fetch example and closing the window with 5.15.0:

❯ python .\examples\aiohttp_fetch.py
DEBUG:asyncio:Using proactor: _IocpProactor
.\examples\aiohttp_fetch.py:40: DeprecationWarning: The object should be created from async function
  self.session = aiohttp.ClientSession(
DEBUG:qasync._windows._EventPoller:Starting (proactor: <_IocpProactor overlapped#=0 result#=0>)...
DEBUG:qasync._windows._EventWorker:Thread started
DEBUG:qasync._QEventLoop:Starting Qt event loop
DEBUG:qasync._QEventLoop:Registering callback <TaskStepMethWrapper object at 0x000002BA224C5CA0> to be invoked with arguments () after 0 second(s)
DEBUG:qasync._SimpleTimer:Registering timer id 4
DEBUG:qasync._SimpleTimer:Timer event on id 4
DEBUG:qasync._SimpleTimer:Calling handle <Handle <TaskStepMethWrapper object at 0x000002BA224C5CA0>()>
DEBUG:qasync._QEventLoop:Qt event loop ended with result 0
DEBUG:qasync._windows._EventPoller:Stopping worker thread...

The expected output when running with 5.14.1 or 5.14.2.2:

❯ python .\examples\aiohttp_fetch.py
DEBUG:asyncio:Using proactor: _IocpProactor
.\examples\aiohttp_fetch.py:40: DeprecationWarning: The object should be created from async function
  self.session = aiohttp.ClientSession(
DEBUG:qasync._windows._EventPoller:Starting (proactor: <_IocpProactor overlapped#=0 result#=0>)...
DEBUG:qasync._windows._EventWorker:Thread started
DEBUG:qasync._QEventLoop:Starting Qt event loop
DEBUG:qasync._QEventLoop:Registering callback <TaskStepMethWrapper object at 0x000001E7703EC6D0> to be invoked with arguments () after 0 second(s)
DEBUG:qasync._SimpleTimer:Registering timer id 3
DEBUG:qasync._SimpleTimer:Timer event on id 3
DEBUG:qasync._SimpleTimer:Calling handle <Handle <TaskStepMethWrapper object at 0x000001E7703EC6D0>()>
DEBUG:qasync._QEventLoop:Qt event loop ended with result 0
DEBUG:qasync._windows._EventPoller:Stopping worker thread...
DEBUG:qasync._windows._EventWorker:Exiting thread
DEBUG:qasync._QEventLoop:Already stopped
DEBUG:qasync._QEventLoop:Closing event loop...
DEBUG:qasync._windows._IocpProactor:Closing
DEBUG:qasync._SimpleTimer:Stopping timers
❯ 

Python version used above is 3.8.3 64-bit , on Windows 10 version 1909.

[Systemcluster]

With PySide2 5.15.1 this issue doesn't appear anymore.