IPv6 addresses need to be wrapped in square brackets ([ ])

When using a IPv6 address as internal_lb_vip_address, it needs to be wrapped in square brackets.
Ansible has the function ipwrap for this. https://docs.ansible.com/ansible/latest/user_guide/playbooks_filters_ipaddr.html#wrapping-ipv6-addresses-in-brackets

Because I have no access currently to openstack ansible repositories, I did it like this

find /opt/openstack-ansible/ -exec sed -i 's/{{ \[internal_lb_vip_address\] }}/{{ \[internal_lb_vip_address\] | ipwrap }}/g' {} \;

find /opt/openstack-ansible/ -exec sed -i 's/{{ internal_lb_vip_address }}/{{ internal_lb_vip_address | ipwrap }}/g' {} \;

find /opt/openstack-ansible/ -exec sed -i 's/{{internal_lb_vip_address}}/{{ internal_lb_vip_address | ipwrap }}/g' {} \;

find /opt/openstack-ansible/ -exec sed -i 's/{{ external_lb_vip_address }}/{{ external_lb_vip_address | ipwrap }}/g' {} \;

After these changes I can now use a IPv6 address as internal_lb_vip_address and external_lb_vip_address.
And no, this is not the complete way to have openstack-ansible support IPv6. Currently dual stack is needed.