POC - Add ip as an option to listeners

[shaun-nx]

As an engineer, I would like to have the option to set a specific IP for a listener so that I can create traffic rules for resources with static IP addresses.

### UACs
- [x] Allow for a listener to be defined with the same port, and different IP address

[github-actions]

Hi @shaun-nx thanks for reporting!

Be sure to check out the docs and the Contributing Guidelines while you wait for a human to take a look at this 🙂

Cheers!

[AlexFenlon]

Closing in favour of implementation of ip listener: #6067

Here is a describe of the GlobalConfiguration when ip listener is enabled.

kubectl describe gc my-release-nginx-ingress-controller
Name:         my-release-nginx-ingress-controller
Namespace:    default
Labels:       app.kubernetes.io/instance=my-release
              app.kubernetes.io/managed-by=Helm
              app.kubernetes.io/name=nginx-ingress
              app.kubernetes.io/version=3.7.0
              helm.sh/chart=nginx-ingress-1.4.0
Annotations:  meta.helm.sh/release-name: my-release
              meta.helm.sh/release-namespace: default
API Version:  k8s.nginx.org/v1
Kind:         GlobalConfiguration
Metadata:
  Creation Timestamp:  2024-07-25T13:33:40Z
  Generation:          3
  Resource Version:    20914
  UID:                 9bd8c5a7-fbb2-4272-b8e9-589f22ad78e7
Spec:
  Listeners:
    Ip:        127.0.0.1
    Name:      http-8084
    Port:      8084
    Protocol:  HTTP
Events:
  Type    Reason   Age               From                      Message
  ----    ------   ----              ----                      -------
  Normal  Updated  58m               nginx-ingress-controller  GlobalConfiguration default/my-release-nginx-ingress was updated
  Normal  Updated  1s (x3 over 58m)  nginx-ingress-controller  GlobalConfiguration default/my-release-nginx-ingress-controller was added or updated

This is the output snippet of the nginx.conf without the ip listener in GlobalConfiguration

...
server {
    listen 8084;
    listen [::]:8084;


    server_name cafe.example.com;

    set $resource_type "virtualserver";
    set $resource_name "cafe";
    set $resource_namespace "default";
...

This is the output snippet of the nginx.conf with the ip listener in GlobalConfiguration

...
server {
    listen 127.0.0.1:8084;
    listen [::]:8084;


    server_name cafe.example.com;

    set $resource_type "virtualserver";
    set $resource_name "cafe";
    set $resource_namespace "default";
...