[Direct Edit] Handle HTTPError 404 (Not Found) errors

HTTPError: 404 Client Error: Not Found for url: https://<SUBHOST>.us-west-2.amazonaws.com/...
  File "nuxeo/client.py", line 305, in request
  File "requests/models.py", line 943, in raise_for_status

HTTPError: HTTPError(404), error: b'<?xml version="1.0" encoding="UTF-8"?>\n<Error><Code>NoSuchVersion</Code><Message>The specified version does not exist.</Message><Key>...</Key><VersionId>...</VersionId><RequestId>...</RequestId><HostId>...</HostId></Error>', server trace: None
  File "nxdrive/direct_edit.py", line 599, in edit
  File "nxdrive/direct_edit.py", line 585, in edit
  File "nxdrive/direct_edit.py", line 525, in _prepare_edit
  File "nxdrive/direct_edit.py", line 351, in _download
  File "nxdrive/client/remote_client.py", line 339, in download
  File "nuxeo/client.py", line 308, in request