PALS CUTOVER: Copy persistent volume claims

[ShanaLMoore]

Original Title: Thumbnails should persist when cuting over to Valkyrie

We deployed knapsack valkyrie to staging and all of the thumbnails disappeared.

Update:
This is not a code issue after all. We need to copy over the persistent volume from pals-staging to palni-knapsack-staging. We'll need to do the same when we cutover for prod.

[ShanaLMoore]

we need to copy the derivative files over for the thumbnails to not go away