Adjust APS MONIT metrics streaming

Based on Nikodemas report:

We have created a dashboard with the new [APS dashboard](https://monit-grafana.cern.ch/goto/56OHPigHg?orgId=11) (original dashboard is [here](https://monit-grafana.cern.ch/goto/7-nhEmRHR?orgId=11)). A few things about the fields in the new dashboard/logs with the examples:

- missing `data.cmsweb_env` - k8s-preprod value in the original dashboard, no alternatives in the new dashboard
- missing `data.cmsweb_cluster` - cmsweb-testbed value in the original dashboard, but data.x_forwarded_host could work as it currently has the value of cmsweb-test10.cern.ch in the new dashboard
- missing `data.client_version` - v002 value in the original dashboard, but we could use data.user_agent in the new dashboard that has a value of WMCore.Services.Requests/v002
- missing `data.proxy_server` - x509-proxy-server or aps-proxy-server, no alternatives in the new dashboard

We need to implement those to be compatible with APS+filebeat+logstash approach used in APS timber dashboard.