Moves GAR menu item below the Container Registry menu item

What does this MR do and why?

Addresses #425154 (comment 1742632871)

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Before	After

How to set up and validate locally

1. Enable container registry in the gdk https://gitlab.com/gitlab-org/gitlab-development-kit/-/blob/main/doc/howto/registry.md#set-up-container-registry-to-display-in-ui-only

2. Simulate a SAAS instance in local GDK

3. In rails console enable the experiment

   Feature.enable(:gcp_artifact_registry)

4. Confirm the sidebar menu item Project > Deploy > Google Artifact registry is below Container registry

Related to #425154 (closed)