Increase PVC claim size persistent storage space

Basic steps:

• shut down apps using storage
• backup current storage content (you can use oc login + oc get pods + oc rsync :/
• create a new pvc for under a new name
• update the deployment config and add the new pvc to be mounted under a new name (volume and volumeMounts)
• oc rsh into the pod and verify both mounts are there (or check in the pathfinder gui)
• oc rsh to pod and copy content to new mount
• update the deployment config and remove old mount and mount new increased pvc to old location.
• verify

See write-up by Kuan Fan at

https://github.com/bcgov/gwells/wiki/Increase-PostgreSQL-Database-storage

for a good example for a postgress pvc increase.