Application metrics that are sums show N/A if any component is not present

[jpswinski]

On the grafana dashboard for the SlideRule Node Application Metrics, there are sometimes N/A's displayed for metrics that should be valid. The reason is that some displays are sums of metrics, and if any one of those metrics hasn't shown up yet, then it makes the entire expression N/A.

For example:

total atl03 granules = atl03s_count{job="orchestrator_app"} + atl06_count{job="orchestrator_app"} + atl08_count{job="orchestrator_app"}

So if we have only atl06_count metrics, the expression shows N/A even though we have processed atl03 granules.