Merge branch '467946-ai-impact-expose-monthly-duo-chat-usage-data-part-2' into 'master'

Add GraphQL API for Duo Pro seats assigned

See merge request https://gitlab.com/gitlab-org/gitlab/-/merge_requests/159428



Merged-by: Adam Hegyi <ahegyi@gitlab.com>
Approved-by: Harsimar Sandhu <hsandhu@gitlab.com>
Approved-by: Adam Hegyi <ahegyi@gitlab.com>
Reviewed-by: Pavel Shutsin <pshutsin@gitlab.com>
Reviewed-by: Josianne Hyson <jhyson@gitlab.com>
Co-authored-by: Pavel Shutsin <pshutsin@gitlab.com>