Kibana misconfiguration can cause Fleet errors.

[naemono]

There appear to be Kibana settings that can cause the operator to fail to check Kibana's Fleet api which in turn causes errors which causes reconciliation delays or reconciliation failures for Elastic Agent Fleet.:

example

apiVersion: kibana.k8s.elastic.co/v1
kind: Kibana
spec:
  config:
    xpack.security.authc.providers:
      saml.saml1:
        order: 0
        realm: saml1

potentially related:

apiVersion: kibana.k8s.elastic.co/v1
kind: Kibana
spec:
  config:
    xpack.security.authc.http.schemes:
    - apikey
    - bearer
    - basic

The relevant error from the logs:

Reconciliation error: failed to request https://kibana-kb-http.namespace.svc:5601/api/fleet/setup, status is 401)

This seems to disable basic authentication provider, which ECK uses to query the Kibana api.

Potential changes to discuss:

1. Maybe use another provider such as bearer/apikey, but what's stopping that from being disabled as well?
2. Add validation which prevents Kibana from being configured in this manner.