Additional labels in ipfs-cluster

[GuillaumeOuint]

Hi,

In your chart "ipfs-cluster", we can't add more labels to the cluster pod (statefulset).
It would be nice to have the possibility to add more labels.

For example, I want to add prometheus labels to auto scrape the metrics. Impossible now if I don't use selector labels (they are shared with the ipfs pod, that can't be monitored so can't use selector labels).