Discuss adjusting setting the `server.name` for Kibana instances.

[naemono]

We currently set the config.server.name for Kibana instances to the name of the Kibana CRD. Code link. Some Kibana documentation indicates that the server.name needs to be distinct for each instance behind a load balancer. This hasn't changed for ~6 years, but also causes issues in stack monitoring where the Kibana instances (if > 1) show up as the Kibana CRD name and not the Pod name.

Potential solutions:

1. Just not set it. The documentation suggests that it defaults to the hostname.
2. Set this via the downward api:

  podTemplate:
    spec:
      containers:
      - name: kibana
        env:
        - name: SERVER_NAME
          valueFrom:
            fieldRef:
              fieldPath: metadata.name

[naemono]

I think the simplest path forward is to just not set this at all, as evidenced in #8930.