Unable to delete SSO user in V3

[JMMolenaar]

In Vulture V3, gui 1.75, Engine-2.4.41-69 clicking on the trash next to a SSO user (in the MongoDB) and confirming, results in a json/ python error:

`TypeError at /repository/sso_profiles/delete/ the JSON object must be str, bytes or bytearray, not NoneType

Request Method:	POST
https://vulture:8000/repository/sso_profiles/delete/USERINFO
1.8
TypeError
the JSON object must be str, bytes or bytearray, not NoneType
/usr/local/lib/python3.7/json/init.py in loads, line 341
/home/vlt-gui/env/bin/python
3.7.6
['/home/vlt-gui/vulture', '/usr/local/lib/python37.zip', '/usr/local/lib/python3.7', '/usr/local/lib/python3.7/lib-dynload', '/home/vlt-gui/env/lib/python3.7/site-packages', '/home/vlt-gui/env/lib/python3.7/site-packages/M2Crypto-0.35.2-py3.7-freebsd-12.1-RELEASE-p1-amd64.egg', '/home/vlt-gui/vulture', '/home/vlt-gui/vulture/vulture/', '/home/vlt-gui/vulture', '/home/vlt-gui/vulture', '/home/vlt-gui/vulture', '/home/vlt-gui/vulture', '/home/vlt-gui/vulture', '/home/vlt-gui/vulture', '/home/vlt-gui/vulture', '/home/vlt-gui/vulture', '/home/vlt-gui/vulture', '/home/vlt-gui/vulture', '/home/vlt-gui/vulture', '/home/vlt-gui/vulture', '/home/vlt-gui/vulture', '/home/vlt-gui/vulture', '/home/vlt-gui/vulture', '/home/vlt-gui/vulture']

`