docs: Correct wrong permission table for container registry

What does this MR do and why?

The GitLab documentation incorrectly states that project developers are allowed to delete container images, see GitLab permissions documentation.

However, the actual implementation only allows maintainers, owners, and admins to delete container images. This is verified by:

• Existing tests in project_container_repositories_spec.rb
• Project policy definition in project_policy.rb

This MR intends to update the documentation to accurately reflect that only maintainers and higher roles can delete container images. This will prevent confusion for users who rely on the documentation for permission management.

Changelog: other

🛠️ with ❤️ at Siemens

Note: There is an inconsistency. Via the frontend developers are able to delete container images, i.e. mark as deleted. But this is not possible through the REST API.

Where does the implementation does it

References

Please include cross links to any resources that are relevant to this MR This will give reviewers and future readers helpful context to give an efficient review of the changes introduced.

• https://docs.gitlab.com/user/permissions/#packages-and-registry
• https://gitlab.com/gitlab-community/gitlab/-/blob/master/spec/requests/api/project_container_repositories_spec.rb#L123
• https://gitlab.com/gitlab-community/gitlab/-/blob/master/app/policies/project_policy.rb#L617

MR acceptance checklist

Please evaluate this MR against the MR acceptance checklist. It helps you analyze changes to reduce risks in quality, performance, reliability, security, and maintainability.

MR Checklist (@gerardo-navarro)

• Changelog entry added, if necessary
• Documentation created/updated via this MR
• Documentation reviewed by technical writer or follow-up review issue created
• Tests added for this feature/bug
• Tested in all supported browsers
• Conforms to the code review guidelines
• Conforms to the style guides
• Conforms to the javascript style guides
• Conforms to the database guides
• Conforms to the merge request performance guidelines

Screenshots or screen recordings

Only changes in the documentation.

How to set up and validate locally

1. Ensure there is a container image in the container registry for a project.
2. Create an access token for a user that has the user role developer for the project.

Numbered steps to set up and validate the change are strongly suggested.

Related to #406797