Remove create group option from duo pro trials

See merge request https://gitlab.com/gitlab-org/gitlab/-/merge_requests/147843



Merged-by: Doug Stull <dstull@gitlab.com>
Approved-by: Serhii Yarynovskyi <syarynovskyi@gitlab.com>
Approved-by: Javiera Tapia <jtapia@gitlab.com>
Reviewed-by: Doug Stull <dstull@gitlab.com>