network: Fix OWE settings

Enhanced Open (OWE) is not being saved properly from connection-editor.
When we create a Wi-Fi connection using Enhanced Open (OWE) Security
from nm-connection-editor and save it, it was not being saved and the
security was being set as "None", with Wireless Security Setting
being discarded. This is fixed by this commit. The fix is also being
done in libnma (implementing OWE in libnma,
https://gitlab.gnome.org/GNOME/libnma/-/issues/9), but this commit
fixes meanwhile it gets ready.

It was solved by adding treatment for the case in which owe was set.
OWE is not treated anymore in the same case as None.

https://gitlab.gnome.org/GNOME/gnome-control-center/-/issues/1521