support namespaces with just numerals in their names

[jmazzitelli]

fixes: kiali/kiali#7773

[jmazzitelli]

to test:

1. have a k8s cluster with istio installed
2. build and push and deploy everything to the cluster : make -e CLUSTER_TYPE=minikube build build-ui cluster-push operator-create kiali-create
3. Now create a namespace with just numbers in the name: kubectl create ns 12345
4. Edit the kiali CR and set CWA=false and include the new namespace in discovery selectors:

kubectl edit kiali kiali -n kiali-operator

spec:
  deployment:
    cluster_wide_access: false
    discovery_selectors:
      default:
      - matchLabels:
        kubernetes.io/metadata.name: "12345"

5. Everything should install fine now.

Look at the Kiali CR and make sure no errors are in the status field (kubectl get kiali kiali -n kiali-operator -oyaml). Also see that the status.deployment.discoverySelectorNamespaces field includes the new 12345 namespace:

$ kubectl get kiali kiali -n kiali-operator -ojsonpath={.status.deployment} | jq
{
  "discoverySelectorNamespaces": "12345,istio-system",
  "instanceName": "kiali",
  "namespace": "istio-system"
}

Bring up the Kiali UI and confirm that you can namespace 12345:
overview page:

graph namespace dropdown:

[jmazzitelli]

molecule tests pass:

make -e CLUSTER_TYPE=minikube MINIKUBE_PROFILE=ci build cluster-push && \
./hack/run-molecule-tests.sh --client-exe "$(which kubectl)"  \
  --minikube-exe $(which minikube) --minikube-profile ci \
   --cluster-type minikube -udi true

=====================
=== TEST RESULTS: ===
=====================

              accessible-namespaces-test... success [6m 43s]
     affinity-tolerations-resources-test... success [3m 17s]
                cluster-wide-access-test... success [7m 30s]
                      config-values-test... success [2m 22s]
                  default-namespace-test... success [1m 44s]
                            grafana-test... success [3m 11s]
                        header-auth-test... success [1m 39s]
                      instance-name-test... success [2m 2s]
                             jaeger-test... success [2m 24s]
                            metrics-test... success [3m 32s]
                     null-cr-values-test... success [1m 35s]
                only-view-only-mode-test... success [2m 20s]
                             openid-test... success [1m 44s]
                   os-console-links-test... skipped
          ossmconsole-config-values-test... skipped
                 read-certs-secrets-test... success [1m 34s]
                              roles-test... success [4m 47s]
                    rolling-restart-test... success [2m 19s]
                              token-test... success [1m 58s]

[aljesusg]

LGFM