[AMQ Streams] Some alerts in Prometheus are send even when specific component is not used

Issue

• Example Prometheus configuration file distributed by Red Hat (prometheus-rules.yaml) contains several optional alerts.
• The alerts will work even when specific component is not installed. This means the user will see "false" alerts for components not present or used in Kafka deployment.
• Consider this example alert:

 - name: bridge
    rules:
    - alert: BridgeContainersDown
      expr: absent(container_last_seen{container=~".+-bridge",pod=~".+-bridge-.+"})
      for: 3m
      labels:
        severity: major
      annotations:
        summary: 'All Kafka Bridge containers down or in CrashLookBackOff status'
        description: 'All Kafka Bridge containers have been down or in CrashLookBackOff status for 3 minutes'

• Even when Kafka Bridge is not used at all, Prometheus will still give alerts.