Kubectl plugin backends does not show backends for TCP and UDP services

[balonik]

What happened:

When using kubectl ingress plugin and trying to list backends, backends for TCP and UDP Services are not listed.

What you expected to happen:

Backends for TCP and UDP Services are listed.

NGINX Ingress controller version (exec into the pod and run nginx-ingress-controller --version.):

-------------------------------------------------------------------------------
NGINX Ingress controller
  Release:       v1.10.0
  Build:         71f78d49f0a496c31d4c19f095469f3f23900f8a
  Repository:    https://github.com/kubernetes/ingress-nginx
  nginx version: nginx/1.25.3

-------------------------------------------------------------------------------

Kubernetes version (use kubectl version):

Client Version: version.Info{Major:"1", Minor:"27+", GitVersion:"v1.27.13-dispatcher", GitCommit:"2632c48320ca08c72387a6e291ec482e2aca4adf", GitTreeState:"clean", BuildDate:"2024-05-06T06:39:51Z", GoVersion:"go1.21.9", Compiler:"gc", Platform:"linux/amd64"}
Kustomize Version: v5.0.1
Server Version: version.Info{Major:"1", Minor:"27+", GitVersion:"v1.27.13-eks-3af4770", GitCommit:"4873544ec1ec7d3713084677caa6cf51f3b1ca6f", GitTreeState:"clean", BuildDate:"2024-04-30T03:31:44Z", GoVersion:"go1.21.9", Compiler:"gc", Platform:"linux/amd64"}

Environment:

$ kubectl krew list
PLUGIN         VERSION
ingress-nginx  v0.31.0
krew           v0.4.3

How to reproduce this issue:

1. deploy Nginx Ingress
2. configure TCP service as documented
3. check that server is added to nginx.conf
4. run kubectl ingress-nginx backends

Anything else we need to know:

Server entry exists in nginx.conf

# TCP services

        server {
                preread_by_lua_block {
                        ngx.var.proxy_upstream_name="tcp-default-selenium-5900";
                }

                listen                  5900 proxy_protocol;

                listen                  [::]:5900 proxy_protocol;

                proxy_timeout           600s;
                proxy_next_upstream     on;
                proxy_next_upstream_timeout 600s;
                proxy_next_upstream_tries   3;

                proxy_pass              upstream_balancer;

        }

[k8s-ci-robot]

This issue is currently awaiting triage.

If Ingress contributors determines this is a relevant issue, they will accept it by applying the triage/accepted label and provide further guidance.

The triage/accepted label can be added by org members by writing /triage accepted in a comment.

Instructions for interacting with me using PR comments are available [here](https://git.k8s.io/community/contributors/guide/pull-requests.md). If you have questions or suggestions related to my behavior, please file an issue against the [kubernetes-sigs/prow](https://github.com/kubernetes-sigs/prow/issues/new?title=Prow%20issue:) repository.

[github-actions[bot]]

This is stale, but we won't close it automatically, just bare in mind the maintainers may be busy with other tasks and will reach your issue ASAP. If you have any question or request to prioritize this, please reach #ingress-nginx-dev on Kubernetes Slack.