feat: use zstd instead of gz by default, fix the backup script

[brokenpip3]

Changes

• Fix backup script: in case of warnings (like files changes while reading) do not fail the backup
• Use zstd by default should be faster than gz especially in situations where you have a lot of jobs

Submitter Checklist

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• [x] Includes tests (if functionality changed/added)
• [ ] Includes docs (if user facing)
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Reviewer Notes

If API changes are included, additive changes must be approved by at least two OWNERS and backwards incompatible changes must be approved by more than 50% of the OWNERS.

Release Notes

* Fix backup script: in case of warnings (like files changes while reading) do not fail the backup
* Use zstd by default should be faster than gz especially in situations where you have a lot of jobs