fix(observability): configure ServiceMonitor for ASO secure metrics authentication

- Update azureserviceoperator-controller-manager-metrics-monitor to use HTTPS scheme
- Add bearerTokenFile authentication using ServiceAccount token
- Configure TLS with insecureSkipVerify for self-signed certificates
- Resolves 401 Unauthorized errors when Prometheus scrapes ASO metrics

The Azure Service Operator exposes secure metrics by default on HTTPS port 8443
requiring proper authentication. This change aligns with ASO documentation at
https://azure.github.io/azure-service-operator/guide/metrics/ which states
"A ServiceAccount token is required to scrape metrics securely".

Fixes: ASO metrics like go_memstats_sys_bytes not appearing in Prometheus
Signed-off-by: Bryan Cox <[email protected]>

Author: bryan-cox

hack/observability/prometheus/resources/prometheus.yaml

@@ -105,7 +105,10 @@ spec:
   endpoints:
     - path: /metrics
       port: metrics
-      scheme: http
+      scheme: https
+      bearerTokenFile: /var/run/secrets/kubernetes.io/serviceaccount/token
+      tlsConfig:
+        insecureSkipVerify: true
   selector:
     matchLabels:
       control-plane: controller-manager