Do not query group level work items on IssuesFinder

See merge request https://gitlab.com/gitlab-org/gitlab/-/merge_requests/145181



Merged-by: Heinrich Lee Yu <heinrich@gitlab.com>
Approved-by: Eulyeon Ko <5961404-euko@users.noreply.gitlab.com>
Approved-by: Mario Celi <mcelicalderon@gitlab.com>
Approved-by: Heinrich Lee Yu <heinrich@gitlab.com>
Co-authored-by: Felipe Artur <felipefac@gmail.com>