Backport: Skopeo auth to registry, via CI_JOB_TOKEN (19-0-stable)

What does this MR do?

Fix fetch_assets to authenticate skopeo inspect for private registries

See merge request !2944 (merged)

(cherry picked from commit 9ff7c3ef)

ce808240 Fix fetch_assets to authenticate skopeo inspect for private registries

Bring this into 19-0 where we currently have a red branch build due to assets detection failing authentication.

Related issues

Checklist

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Expected (please provide an explanation if not completing)

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