Add example of Control Center connected to Confluent Cloud using service account

[vdesabou]

See doc

[vdesabou]

There is actually an example to do that using ccloud CLI here:

function ccloud::create_acls_control_center() {
  serviceAccount=$1

  echo "Confluent Control Center: creating _confluent-command and ACLs for service account $serviceAccount"
  ccloud kafka topic create _confluent-command --partitions 1

  ccloud kafka acl create --allow --service-account $serviceAccount --operation WRITE --topic _confluent --prefix
  ccloud kafka acl create --allow --service-account $serviceAccount --operation READ --topic _confluent --prefix
  ccloud kafka acl create --allow --service-account $serviceAccount --operation CREATE --topic _confluent --prefix

  ccloud kafka acl create --allow --service-account $serviceAccount --operation READ --consumer-group _confluent --prefix
  ccloud kafka acl create --allow --service-account $serviceAccount --operation WRITE --consumer-group _confluent --prefix
  ccloud kafka acl create --allow --service-account $serviceAccount --operation CREATE --consumer-group _confluent --prefix

  return 0
}

Which is used in there