Skip parallel files upload and download test for Restic case.

[blackpiglet]

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Fixes #(issue)

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[codecov[bot]]

Codecov Report

All modified and coverable lines are covered by tests :white_check_mark:

Project coverage is 58.79%. Comparing base (b9b21b5) to head (9b7dd66).

Additional details and impacted files

```diff @@ Coverage Diff @@ ## main #7879 +/- ## ======================================= Coverage 58.79% 58.79% ======================================= Files 345 345 Lines 28765 28765 ======================================= Hits 16913 16913 Misses 10423 10423 Partials 1429 1429 ```

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