Docs: Clarify container registry project transfer steps

doc/user/packages/container_registry/index.md

@@ -626,13 +626,18 @@ Use your own URLs to complete the following steps:
    docker pull gitlab.example.com/org/build/sample_project/cr:v2.9.1
    ```
 
+NOTE:
+For container registry authentication, use either a
+[personal access token](../../profile/personal_access_tokens.md) or a
+[deploy token](../../project/deploy_tokens/index.md).
+
 1. Rename the images to match the new project name:
 
    ```shell
    docker tag gitlab.example.com/org/build/sample_project/cr:v2.9.1 gitlab.example.com/new_org/build/new_sample_project/cr:v2.9.1
    ```
 
-1. Delete the images in both projects by using the [UI](#delete-images) or [API](../../../api/packages.md#delete-a-project-package).
+1. Delete the images in the old project by using the [UI](#delete-images) or [API](../../../api/packages.md#delete-a-project-package).
    There may be a delay while the images are queued and deleted.
 1. Change the path or transfer the project by going to **Settings > General**
    and expanding **Advanced**.