[chart] Set autoscaling.minReplica=2 by default

[AndersBennedsgaard]

By default, autoscaling.enabled=true, autoscaling.minReplica=1, podDisruptionBudget.enabled=true, and podDisruptionBudget.minAvailable=1.

This means that since (by default) the HPA allows autoscaling to 1 replica, you might get errors when patching nodes, since kubectl drain will try to remove the single Cortex Tenant pod, which the PDB doesn't allow.

The workaround is simple; set autoscaling.minReplica=2 or disable the PDB.
However, it would be nice if the chart is possible to deploy to a cluster with as few changes as possible, so I would like the chart to have autoscaling.minReplica=2 by default. What do you think of this?

[blind-oracle]

Sorry for late answer.
I have no problems with that, but since I don't use k8s at all, I have no strong opinion. If you want to change that - please make a PR :)