Merge branch 'el-create-base-iv-controller' into 'master'

Move reusable Identity Verification controller code to a base controller

See merge request https://gitlab.com/gitlab-org/gitlab/-/merge_requests/145635



Merged-by: Alex Pooley <apooley@gitlab.com>
Approved-by: Ross Byrne <robyrne@gitlab.com>
Approved-by: Harsha Muralidhar <hmuralidhar@gitlab.com>
Approved-by: Ian Anderson <ianderson@gitlab.com>
Approved-by: Grzegorz Bizon <grzegorz@gitlab.com>
Approved-by: Smriti Garg <sgarg@gitlab.com>
Approved-by: Alex Pooley <apooley@gitlab.com>
Reviewed-by: Grzegorz Bizon <grzegorz@gitlab.com>
Reviewed-by: Ian Anderson <ianderson@gitlab.com>
Co-authored-by: Eugie Limpin <elimpin@gitlab.com>