Registry Enhancements

[iwilltry42]

As per internal Slack discussion, we want to introduce the following changes:

1. Garbage Collect unused tags on some interval. - Not happening for now because we uncovered more and more pitfalls around this and we'll probably start on the manager side for this
2. Start the internal registry backed by an actual PV if a default storage class is present (10G size - no configuration options)

[sangee2004]

Tested with acorn version - v0.8.0-rc4+b6a95e8a

In my local cluster, local-path is the default storage provider.

 kubectl get storageclass
NAME                   PROVISIONER             RECLAIMPOLICY   VOLUMEBINDINGMODE      ALLOWVOLUMEEXPANSION   AGE
local-path (default)   rancher.io/local-path   Delete          WaitForFirstConsumer   false                  165d

Registry has a PVC in the acorn-image-system

kubectl get pvc -n acorn-image-system
NAME       STATUS   VOLUME                                     CAPACITY   ACCESS MODES   STORAGECLASS   AGE
registry   Bound    pvc-2cf2be60-f2ef-4408-b41a-caee8b6d1e58   10Gi       RWO            local-path     22h