I have a golang test that setup multiple stand alone docker containers using dockertest lib, and a k8s cluster that I setup using k3s.
As part of the test, I’m creating a docker network with name “my-docker-network”. I need the docker containers to be able to access the k8s cluster, how can I do that?
For example:

func setup(ctx context.Context, pool *dockertest.Pool, network *dockertest.Network) error {
    resource, err := pool.RunWithOptions(&dockertest.RunOptions{
        Name:       myContainerName,
        Repository: "my-container-repo",
        Tag:        "my-tag",
        Networks:   []*dockertest.Network{network},
    })
    if err != nil {
        // ....
    }

    k3sContainer, err := k3s.Run(ctx, "docker.io/rancher/k3s:v1.27.1-k3s1",
        network.WithNetwork([]string{}, &testcontainers.DockerNetwork{Name: network.Network.Name}),
        testcontainers.WithConfigModifier(func(config *container.Config) {
            config.Cmd = []string{
                "server",
                "--disable=traefik",
                "--tls-san=host.docker.internal",
            }
        }))
    if err != nil {
        // ....
    }
    
    // ...
}

In the docker container, I have this code:

    decodedCert, err := b64.StdEncoding.DecodeString(clusterCa)
    if err != nil {
        log.Fatal(err)
    }
    k8sConf := &rest.Config{
        Host:            clusterEndpoint,
        BearerToken:     accessToken,
        TLSClientConfig: rest.TLSClientConfig{CAData: decodedCert},
    }
    k8sClient, err := kubernetes.NewForConfig(k8sConf)
    if err != nil {
        log.Fatal(err)

    }

    _, err = k8sClient.Discovery().RESTClient().Get().AbsPath("/healthz").DoRaw(context.Background())
    if err != nil {
        log.Fatal("Failed to get k8s /healthz", err)
    }

Which return error:
Failed to get k8s /healthzGet "https://localhost:62034/healthz": dial tcp connect: connection refused

Everything work as expected when I try this code in localhost, so it’s not issue with the certificate or token, I’m also able to make it work by calling https://host.docker.internal:62034/healthz, however it’s not working in a github runner (“dial tcp: lookup host.docker.internal on 127.0.0.150:53: no such host”).
I wonder how I can setup k3s in a way that I will be able to call it from other docker containers in the same network using https://my-k3s-container:{EXPOSED_PORT}, like I’m doing with the docker containers- I’m able to comminucate between two containers by using the conatiner name I’m passing in dockertest.RunOptions