Add plan badge to Admin -> Groups

What does this MR do and why?

Related to #551933 (closed) and Migrate admin area groups list to Vue shared co... (&17783 - closed)

We are working on migrating Admin -> Groups from HAML/Vanilla JS to Vue with a GraphQL data source. This will help us reduce technical debit and have consistent UX across all the group and project lists.

The HAML version displays plan badges on SaaS. This MR implements the same badges on the Vue version.

References

Screenshots or screen recordings

admin_groups_vue FF disabled	admin_groups_vue FF enabled

How to set up and validate locally

1. Start GDK in SaaS mode - https://docs.gitlab.com/development/ee_features/#simulate-a-saas-instance
2. Go to /rails/features and enable admin_groups_vue feature flag
3. Go to /admin/groups

MR acceptance checklist

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