Skip parallel files upload and download test for Restic case

[blackpiglet]

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[codecov[bot]]

Codecov Report

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

Project coverage is 58.80%. Comparing base (0d36572) to head (200f16e).

Additional details and impacted files

```diff @@ Coverage Diff @@ ## release-1.14 #7860 +/- ## ============================================= Coverage 58.80% 58.80% ============================================= Files 345 345 Lines 28771 28771 ============================================= Hits 16919 16919 Misses 10423 10423 Partials 1429 1429 ```

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