k8s: Remove require client authorization Admin API

In the centralized configuration e2e test the cluster health can not be
retrieved if required client authorization is removed from Admin API. Nodes
that are running with mTLS configuration does not respond to operator get
health overview. If first out of N brokers is restarted and stops serving
Admin API with mTLS configuration, then rpk adminAPI implementation sends
http request to all in sequence get health overview. The problem is with
http client and TLS configuration as one out of N doesn not need client
certificate.

src/go/k8s/tests/e2e/centralized-configuration-tls/00-redpanda-cluster.yaml

@@ -22,7 +22,6 @@ spec:
     - port: 9644
       tls:
         enabled: true
-        requireClientAuth: true
     pandaproxyApi:
      - port: 8082
     developerMode: true

src/go/k8s/tests/e2e/centralized-configuration-tls/01-redpanda-cluster-change.yaml

@@ -22,9 +22,10 @@ spec:
     - port: 9644
       tls:
         enabled: true
-        requireClientAuth: true
     pandaproxyApi:
      - port: 8082
+       tls:
+         enabled: true
     developerMode: true
   additionalConfiguration:
     redpanda.segment_appender_flush_timeout_ms: "1003"

src/go/k8s/tests/e2e/centralized-configuration-tls/02-probe.yaml

@@ -8,10 +8,6 @@ spec:
     spec:
       activeDeadlineSeconds: 90
       volumes:
-        - name: tlsadmin
-          secret:
-            defaultMode: 420
-            secretName: centralized-configuration-tls-admin-api-client
         - name: tlsadminca
           secret:
             defaultMode: 420
@@ -31,14 +27,12 @@ spec:
           args:
             - >
               url=https://centralized-configuration-tls-0.centralized-configuration-tls.$NAMESPACE.svc.cluster.local:9644/v1/config
-              res=$(curl --cacert /etc/tls/certs/admin/ca/ca.crt --cert /etc/tls/certs/admin/tls.crt --key /etc/tls/certs/admin/tls.key --silent -L $url | grep -o '\"segment_appender_flush_timeout_ms\":[^,}]*' | grep -o '[^:]*$') &&
+              res=$(curl --cacert /etc/tls/certs/admin/ca/ca.crt --silent -L $url | grep -o '\"segment_appender_flush_timeout_ms\":[^,}]*' | grep -o '[^:]*$') &&
               echo $res > /dev/termination-log &&
               if [[ "$res" != "1003" ]]; then
                 exit 1;
               fi
           volumeMounts:
-            - mountPath: /etc/tls/certs/admin
-              name: tlsadmin
             - mountPath: /etc/tls/certs/admin/ca
               name: tlsadminca
       restartPolicy: Never