[docs]: Fix network config on debian 12 installed with cloudinit

Hi !
I have a little problem with debian 12 and cloudinit network management :

Network operation with cloud-init changed between debian 11 and debian 12 and the "/etc/network/interfaces" file no longer exists and the networking/systemd-networkd service no longer exists either ...
Impossible to set an IP address as before using the contents of "/etc/network/interfaces.d/50-cloud-init" in "/etc/network/interfaces" ...
How can I fix my network configuration again in "/etc/network/interfaces" after installing the machine using cloudinit in addition to "echo "network: {config: disabled}" > /etc/cloud/cloud.cfg.d/99-disable-network-config.cfg" ?

Thanks in advance !