Bug 422694

SUMMARY
nmcli allows specifying custom IP ranges for shared connections.
plasma-nm does not support this and will overwrite these settings

STEPS TO REPRODUCE
1. Create a new shared ethernet or wifi connection using cli or gui
2. Change ip range using cli: `nmcli connection modify $ID +ipv4.addresses 192.168.5.1/24`
4. Observe change took place: `nmcli connection show $ID | grep ipv4.adresses` yields `ipv4.addresses: 192.168.5.1/24`
3. Activate connection using cli or gui
4. Observe dnsmasq is launched with correct ip: `ps aux | grep dnsmasq` yields ... "--listen-address=192.168.5.1" ...

TRIGGER BUG:
5. Perform any modification in the gui (eg renaming the connection) and press apply

OBSERVED RESULT:
6. `nmcli connection show $ID | grep ipv4.adresses` yields "ipv4.addresses: --"
7. dnsmasq uses default IP range of 10.42.0.1

EXPECTED RESULT:
plasma-nm should not delete ipv4.addresses
6. `nmcli connection show $ID | grep ipv4.adresses` yields "ipv4.addresses: 192.168.5.1/24"
7. dnsmasq still uses the specified range


SOFTWARE/OS VERSIONS
Windows: 
macOS: 
Linux/KDE Plasma: Kubuntu 20.04
KDE Plasma Version:  5.18.5
KDE Frameworks Version: 5.68.0
Qt Version: 5.12.8

ADDITIONAL INFORMATION
NetworkManager version: 1.22.10