(fix) Removing Unused and Insecure Manifests for Prometheus since its integration is not supported

We are not using these manifests or supporting this option. Therefore, they should be removed, as they are not configured to use certificates and have insecureSkipVerify: false, which promotes an insecure setup by default.

If we want enable this option then we need configure it with:

```yaml
apiVersion: monitoring.coreos.com/v1
kind: ServiceMonitor
metadata:
  labels:
    control-plane: operator-controller-controller-manager
  name: controller-manager-metrics-monitor
  namespace: system
spec:
  endpoints:
    - path: /metrics
      port: https
      scheme: https
      bearerTokenFile: /var/run/secrets/kubernetes.io/serviceaccount/token
      tlsConfig:
        insecureSkipVerify: false
        ca:
          secret:
            name: olmv1-cert
            key: ca.crt
        cert:
          secret:
            name: olmv1-cert
            key: tls.cert
        keySecret:
          name: olmv1-cert
          key: tls.key
  selector:
    matchLabels:
      control-plane: operator-controller-controller-manager
```

Author: camilamacedo86

config/base/kustomization.yaml

@@ -18,5 +18,4 @@ resources:
 - crd
 - rbac
 - manager
-# [PROMETHEUS] To enable prometheus monitor, uncomment all sections with 'PROMETHEUS'.
-#- ../prometheus
+