Relocate group usage dashboard from gitlab duo settings

What does this MR do and why?

This relocate group usage dashboard from gitlab duo settings to the parent menu

Previous path	New path
/groups/:groupname/-/settings/gitlab_duo/usage	/groups/:groupname/-/settings/gitlab_credits_dashboard
/groups/:groupname/-/settings/gitlab_duo/usage/users/:username	/groups/:groupname/-/settings/gitlab_credits_dashboard/users/:username

GitLab Duo summary

References

• Related issue: https://gitlab.com/gitlab-org/gitlab/-/issues/580552+
• MR for the Admin Dashboards: Relocate Admin Usage Dashboard from Duo setting... (!214363 - merged)

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