Red Hat Quay fail to start with error: AttributeError: 'NoneType' object has no attribute 'lower'

Issue

• After upgrading to Quay v3.8.5 the quay-app pod fails through the operator deployment:

  023-04-06T07:03:00.992460612Z Running init script '/quay-registry/conf/init/nginx_conf_create.sh'
  2023-04-06T07:03:01.091604872Z Traceback (most recent call last):
  2023-04-06T07:03:01.091604872Z   File "/quay-registry/conf/init/nginx_conf_create.py", line 169, in <module>
  2023-04-06T07:03:01.091687664Z     generate_nginx_config(config)
  2023-04-06T07:03:01.091687664Z   File "/quay-registry/conf/init/nginx_conf_create.py", line 80, in generate_nginx_config
  2023-04-06T07:03:01.091746039Z     use_ipv4 = True if ip_version.lower() != "ipv6" else False
  2023-04-06T07:03:01.091756280Z AttributeError: 'NoneType' object has no attribute 'lower'