Merge branch '439095-users-filter-backend-rte' into 'master'

Allow filtering users on backend in RTE

See merge request https://gitlab.com/gitlab-org/gitlab/-/merge_requests/168040



Merged-by: Simon Knox <simon@gitlab.com>
Approved-by: Simon Knox <simon@gitlab.com>
Co-authored-by: Himanshu Kapoor <hkapoor@gitlab.com>