19.0 Backport: Merge branch 'add-retry-to-manifest-upload' into 'master'

What does this MR do and why?

Describe in detail what merge request is being backported and why

This MR backports !9525 (merged) to 19.0 stable branch which adds retry: 2 to the manifest-upload job in gitlab-ci-config/dev-gitlab-org.yml to improve resilience against transient failures during manifest uploads.

Related issue: #9927 (closed)

MR acceptance checklist

This checklist encourages us to confirm any changes have been analyzed to reduce risks in quality, performance, reliability, security, and maintainability.

• This MR is backporting a bug fix, documentation update, or spec fix, previously merged in the default branch.
• The original MR has been deployed to GitLab.com (not applicable for documentation or spec changes).
• This MR has a severity label assigned (if applicable).

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