Add checkpoint deletion options to configuration and Orbax checkpoint manager

[awonak]

Description

GCS does not support fast deletions. Checkpoint saves would get stuck on force deletion of a large checkpoint directory.

This change introduces the Orbax flag to "rename" old checkpoint saves instead of deleting them directly.

https://orbax.readthedocs.io/en/latest/api_reference/checkpoint.checkpoint_manager.html#checkpointmanageroptions

FIXES: b/485730473

Tests

TBD

Checklist

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