Call RenameRepository instead of RenameNamespace when namespace is renamed

What does this MR do?

corresponding mr: gitlab-foss!32684 (closed)

This MR changes the mv_repository call in shell.rb to use RenameRepository instead of RenameNamespace

This will need gitaly!1471 (merged) to be merged and tagged in a new gitaly version first

Screenshots

Does this MR meet the acceptance criteria?

Conformity

• Changelog entry
• Documentation created/updated or follow-up review issue created
• Code review guidelines
• Merge request performance guidelines
• Style guides
• Database guides
• Separation of EE specific content

Performance and Testing

• Review and add/update tests for this feature/bug. Consider all test levels. See the Test Planning Process.
• Tested in all supported browsers

Security

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• Label as security and @ mention @gitlab-com/gl-security/appsec
• The MR includes necessary changes to maintain consistency between UI, API, email, or other methods
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