macOS: QNetworkInterface returns IP address for interface that no longer has IP

With the introduction of ARM64 macOS machines on CI (the only mentioned because these are real machines, not VMs) and the removal of insignificant in our auto-tests on this platform we noticed a problem. QNetworkInterface in its allInterfaces() returns an interface that is considered to be up and running, has a non-null IPv4 address but actually has IPv4 disabled/off and as a result, when running auto-tests against this interface, we end-up (e.g.) with 'Host-Unreachable'. See the more detailed comment from Tor Arne below. Attempts to use native frameworks are not very successful so far - the results are similar to what getifaddrs gives us.