Add container registry dependency maintainers

What does this MR do?

The container registry team has been managing CNG version updates for a while since gitlab-org/build/CNG!1502 (merged). This MR proposes giving the registry maintainers permissions to merge version bumps on this project as well. This should help speed up the release process and remove load from Distribution maintainers.

Author checklist

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Required

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• Merge Request Title and Description are up to date, accurate, and descriptive.
• MR targeting the appropriate branch.
• MR has a green pipeline.
• Documentation created/updated.
• Tests added/updated, and test plan for scenarios not covered by automated tests.
• Equivalent MR/issue for omnibus-gitlab opened.

Reviewers checklist

• MR has a green pipeline on https://gitlab.com/gitlab-org/charts/gitlab.
• Consider downstream impact to the Operator, as per evaluating impact from changes to GitLab Chart.