add vmbackupmanager suffix to the job label for auto-generated vmservicescrape

[f41gh7]

Currently, operator generates VMServiceScrape config for each port defined at Service. It produces the following configuration for the vmbackupmanager:

  - attach_metadata: {}
    path: /metrics
    port: http
  - attach_metadata: {}
    path: /metrics
    port: vmbackupmanager

It makes produces metrics with the same job name, but different addresses and container names. And it makes metrics hard to use with grafana dashboards that relies only at job labels to distinguish components.

I propose the following changes:

• add port suffix for non default (aka http) ports with relabelConfigs.
• by default generate endpoints only for http and vmbackupamanger ports. Currently it will be generate for the any ports defined at Service.

[f41gh7]

Feature was added at v0.52.0 release