Enable ipv6 for azure-iot-edge user-defined network

[AlesterRune]

We have a Raspberry Pi that we use as an edge device. One of our modules needs to communicate over IPv6 in the local network. Since the module is automatically connected to the "azure-iot-edge" network in Docker, I'd like a method to easily enable IPv6 on this network.

To achieve this, I tried following the steps described in the IPv6Configuration documentation. For me, this worked only for the default bridge network but not for the "azure-iot-edge" network. I also checked the networking documentation and attempted to configure the network using the mentioned /etc/aziot/edged/config.yaml file. However, this file did not exist initially, and when I manually added it, it seemed to be completely ignored.

The only way I have been able to get IPv6 to work for the "azure-iot-edge" network so far is by completely removing it and manually recreating it with IPv6 enabled. This also required me to manually disconnect and later reconnect all modules. This does not feel like the correct way to achieve this. I would assume there should be a way to configure this either from the module definition in the IoT Hub or by adding some configuration on the device.