Don't download artifacts for Secret Detection

Why is this change being made?

Secret Detection started to report findings located in public/. This is because the job downloads by default all artifacts, including in this case the generated public/ folder. Not only this is generating false positives, but the job consumes time and CPU for nothing.

Note that Dependency Scanning has a different behavior: Artifacts are not downloaded by default.

The new job takes less than 2 minutes to run, versus nearly 15 minutes before.

Author Checklist

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