Cannot delete files or folders on a volume in macOS

## Description
On macOs I cannot delete files when operating on an volume (like a Box.app folder).

This error appears:
```
Traceback (most recent call last): File "/Users/tillmann.brodbeck@ibm.com/Library/Python/3.7/lib/python/site-packages/tornado/web.py", line 1699, in _execute result = await result File "/Users/tillmann.brodbeck@ibm.com/Library/Python/3.7/lib/python/site-packages/tornado/gen.py", line 209, in wrapper yielded = next(result) File "/Users/tillmann.brodbeck@ibm.com/Library/Python/3.7/lib/python/site-packages/notebook/services/contents/handlers.py", line 237, in delete yield maybe_future(cm.delete(path)) File "/Users/tillmann.brodbeck@ibm.com/Library/Python/3.7/lib/python/site-packages/notebook/services/contents/manager.py", line 279, in delete self.delete_file(path) File "/Users/tillmann.brodbeck@ibm.com/Library/Python/3.7/lib/python/site-packages/notebook/services/contents/filemanager.py", line 540, in delete_file send2trash(os_path) File "/Users/tillmann.brodbeck@ibm.com/Library/Python/3.7/lib/python/site-packages/send2trash/plat_osx.py", line 48, in send2trash check_op_result(op_result) File "/Users/tillmann.brodbeck@ibm.com/Library/Python/3.7/lib/python/site-packages/send2trash/plat_osx.py", line 37, in check_op_result raise OSError(msg) OSError: File not found
```
## Reproduce
Create a box folder (box.com).
Operate into the box volume and start jupyter notebook/lab
Create a folder and then delete it.

## Expected behavior
Deletion

## Context

I use the latest stable macOS, Chrome and jupyter version.

The traceback points to notebook/services/contents/filemanager.py and send2trash/plat_osx.py. Reproduce the failure by running Jupyter on a Box volume, creating a folder, and deleting it; compare this with deletion on a regular path. Done means files and folders can be deleted successfully on the volume.

Written by the indexing model from the issue text.