Example code fails on Windows 10

I am using a pristine notebook and kernel to run the example from [the documentation](https://ipyparallel.readthedocs.io/en/latest/). Execution fails with error messages.

## Environment
- Jupyter Notebook 6.4.5
- Python 3.8.5
- ipyparallel 8.0.0

## Code
```
import time
import ipyparallel as ipp

task_durations = [1] * 25
# request a cluster
with ipp.Cluster() as rc:
# get a view on the cluster
view = rc.load_balanced_view()
# submit the tasks
asyncresult = view.map_async(time.sleep, task_durations)
# wait interactively for results
asyncresult.wait_interactive()
# retrieve actual results
result = asyncresult.get()
# at this point, the cluster processes have been shutdown
```

## Error
```
Starting 24 engines with
sleep: 16%|█▌ | 4/25 [00:05<00:00, 36.36tasks/s]Failed to remove C:\Users\MyUserName\.ipython\profile_default\log\ipengine-1639155465-zlhr-1639155466-2.log: [WinError 32] The process cannot access the file because it is being used by another process: 'C:\\Users\\MyUserName\\.ipython\\profile_default\\log\\ipengine-1639155465-zlhr-1639155466-2.log'
Failed to remove C:\Users\MyUserName\.ipython\profile_default\log\ipengine-1639155465-zlhr-1639155466-1.log: [WinError 32] The process cannot access the file because it is being used by another process: 'C:\\Users\\MyUserName\\.ipython\\profile_default\\log\\ipengine-1639155465-zlhr-1639155466-1.log'
Failed to remove C:\Users\MyUserName\.ipython\profile_default\log\ipengine-1639155465-zlhr-1639155466-8.log: [WinError 32] The process cannot access the file because it is being used by another process: 'C:\\Users\\MyUserName\\.ipython\\profile_default\\log\\ipengine-1639155465-zlhr-1639155466-8.log'
```
Full output:
[error_output.txt](https://github.com/ipython/ipyparallel/files/7694608/error_output.txt)

Reproduce the documentation example starting at ipp.Cluster() on Windows 10 with the listed Python, Jupyter Notebook, and ipyparallel versions. Inspect error_output.txt and the failed log-removal messages; done means the example completes without WinError 32 cleanup failures.

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