persist: turn on CRDB changefeeds -> s3 for all prod environments

[benesch]

This is an important insurance policy in the case of a data loss disaster.

[benesch]

From discussions with @danhhz and @pH14:

• Paul has an old PR for this: https://github.com/MaterializeInc/cloud/pull/4555
• One pain point in the past was setting up IAM delegation for this instead of using static access keys; plausibly this was fixed when we set up IAM delegation for backups and restores
• Another blocker was that SHOW CHANGEFEED JOBS took like literal minutes to complete. I think this is fixed in v23.1 due to some optimizations they made to not scan the whole jobs table to compute SHOW CHANGEFEED JOBS.

tl;dr is that I'll try to find some time this quarter to revive Paul's PR and see if I can get it across the finish line.