Authentication examples needed in Native Client Security

Hi, I have some feedback about [this page](https://github.com/hazelcast/imdg-docs/edit/v/4.1/docs/modules/security/pages/native-client-security.adoc). Specifically, my feedback is about the [Authentication](https://docs.hazelcast.com/imdg/4.1.1/security/native-client-security.html#authentication) section of that page.

Currently, only the authentication option of `` is shown as an example. However, both the `kerberos` and `credentials-factory` options which are briefly mentioned require configuring many properties, and it's unclear from the documentation how such a thing would be done. I would request examples be added for these two authentication types.