In backup sync flow put snapshotHandle as source in CSI VSContent

[anshulahuja98]

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Does your change fix a particular issue?

Fixes #(issue) https://kubernetes.io/docs/concepts/storage/volume-snapshots/

Context: We have few customers which have used same storage bucket across clusters, as a result of that their VSContents are syncing across clusters, After the sync the other cluster does not have permission on the snapshot of original cluster, it starts to rePUT the snapshot. This leads to significant load on the CSI driver.

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• [ ] Accepted the DCO. Commits without the DCO will delay acceptance.
• [ ] Created a changelog file or added /kind changelog-not-required as a comment on this pull request.
• [ ] Updated the corresponding documentation in site/content/docs/main.

[codecov[bot]]

Codecov Report

Attention: Patch coverage is 0% with 2 lines in your changes missing coverage. Please review.

Project coverage is 58.77%. Comparing base (b0dc189) to head (d1d331f).

Files	Patch %	Lines
pkg/controller/backup_sync_controller.go	0.00%	2 Missing :warning:

Additional details and impacted files

```diff @@ Coverage Diff @@ ## main #7924 +/- ## ========================================== - Coverage 58.79% 58.77% -0.03% ========================================== Files 345 345 Lines 28766 28768 +2 ========================================== - Hits 16914 16908 -6 - Misses 10423 10430 +7 - Partials 1429 1430 +1 ```

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