The apiservers shouldn't expose both SLO and SLI latency metrics to Prometheus

All the apiservers:

• kube-apiserver
• openshift-apiserver
• oauth-apiserver

Expose both `apiserver_request_slo_duration_seconds` and `apiserver_request_sli_duration_seconds`. The SLI metric was introduced in Kubernetes 1.26 as a replacement of `apiserver_request_slo_duration_seconds` which was deprecated in Kubernetes 1.27. This change is only a renaming so both metrics expose the same data. To avoid storing duplicated data in Prometheus, we need to drop the `apiserver_request_slo_duration_seconds` in favor of `apiserver_request_sli_duration_seconds`.