crosscluster/physical: pts metrics not updating

We expose the follow PCR related pts metrics:
```
jobs_replication_stream_producer_protected_age_sec
jobs_history_retention_protected_age_sec
jobs_replication_stream_ingestion_protected_age_sec
jobs_standby_read_ts_poller_protected_age_sec
```

but they do not seem to update during PCR. They should get updated here:
https://github.com/msbutler/cockroach/blob/master/pkg/jobs/metricspoller/poller.go#L90

Also, the standby poller job should not have a pts metric. it should be removed here: https://github.com/msbutler/cockroach/blob/master/pkg/jobs/metrics.go#L452

Jira issue: CRDB-55438