Allow replaying WACZ files from replica storage

[ikreymer]

Add replay_from_replica helm chart value, which, if set, will use the first replica (when available) for replay instead of the primary storage.

[tw4l]

Makes sense and tested as working. Could be nice to eventually be able to choose which replica is used by name but I think first in list is fine for now.

[ikreymer]

Perhaps we want to enable this per-org, rather than per-cluster? The need for this has diminished, since we've figured out a major issue in our slowdown was the CDN on DO.

[tw4l]

Perhaps we want to enable this per-org, rather than per-cluster? The need for this has diminished, since we've figured out a major issue in our slowdown was the CDN on DO.

It's a good point that custom org storages might change this significantly, since we'll have more complexity of which storage is used per-org. Maybe better to hold off until we have a concrete need?

[ikreymer]

Closing for now, let's come back after #578