Cannot enable IPv6 mode on cluster_run node

This is a regression that occurred sometime after 43a050c

I am unable to configure a cluster_run node for IPv6, attempts result in a 400 Bad Request.

Repro steps:

1. IPV6=true ./cluster_run --dont-rename
2. post afamily=ipv6 to /node/controller/setupNetConfig

{"errors":{"_":"Failed to update distribution configuration file. Missing TCP-IPv6 listener (needed for external communication)"}}

Marking as critical, as analytics is forced to remain on pinned SHA from 18-Dec until resolved to avoid breaking IPv6 regression tests.