Resource contention in tests DownloadImageSet

Multiple tests can run concurrently and try to download this resource to the same folder.

## Build Information
Build: https://dev.azure.com/dnceng-public/cbb18261-c48f-4abb-8651-8cdcb5474649/_build/results?buildId=954239
Build error leg or test failing: Microsoft.ML.AutoML.Test.AutoFeaturizerTests.AutoFeaturizer_image_test
Pull request: https://github.com/dotnet/machinelearning/pull/7388

## Error Message

Fill the error message using [step by step known issues guidance](https://github.com/dotnet/arcade/blob/main/Documentation/Projects/Build%20Analysis/KnownIssueJsonStepByStep.md).

```json
{
"ErrorMessage": "flower_photos_tiny_set_for_unit_tests.zip' because it is being used by another process",
"ErrorPattern": "",
"BuildRetry": false,
"ExcludeConsoleLog": true
}
```

### Known issue validation
**Build: :mag_right:** https://dev.azure.com/dnceng-public/public/_build/results?buildId=954239
**Error message validated:** `[flower_photos_tiny_set_for_unit_tests.zip' because it is being used by another process`]
**Result validation:** :white_check_mark: Known issue matched with the provided build.
**Validation performed at:** 2/20/2025 7:12:33 PM UTC

### Report
#### Summary
|24-Hour Hit Count|7-Day Hit Count|1-Month Count|
|---|---|---|
|0|0|0|