Add TLS support to the Operator

[tchughesiv]

Is your feature request related to a problem? Please describe. An Operator user should be able to configure feast with TLS.

Describe the solution you'd like When configured, TLS will be enabled for that feast service. If the operator detects it's running in an OpenShift cluster, we enable TLS by default because we can leverage the built-in service serving certificate feature.

apiVersion: feast.dev/v1alpha1
kind: FeatureStore
metadata:
  name: example
  namespace: <namespace>
spec:
  feastProject: test
  services:
    <feast_service_type>: // e.g. offlineStore, onlineStore, registry 
      // add CRD validation that requires `secretRef` to be set if `disable` is false.
      tls: // optional ... enabled by default when deployed to an OpenShift cluster. if user leaves tls undefined, the operator assumes tls should be enabled and uses built-in service serving certificate feature.
        secretRef: // required if tls.disable is false
          name: <string> // required
        secretKeyNames: // optional
          tlsCrt: <string> // optional (defaults to tls.crt)
          tlsKey: <string> // optional (defaults to tls.key)
        verifyClient: <bool> // optional (defaults to false) currently only used with offline server
        disable: <bool> // optional (defaults to false) allows the user to disable tls without removing the TLS settings. one scenario in which this is beneficial would be in openshift, where we default to tls being enabled

Additional context References for implementation -

https://github.com/feast-dev/feast/blob/master/docs/how-to-guides/starting-feast-servers-tls-mode.md

https://kubernetes.io/docs/tasks/tls/managing-tls-in-a-cluster/

https://docs.openshift.com/container-platform/4.17/security/certificates/service-serving-certificate.html

https://github.com/feast-dev/feast/pull/4677

https://github.com/feast-dev/feast/pull/4744

https://github.com/feast-dev/feast/pull/4718