Merge branch '427183-pages-clean-up-unused-code' into 'master'

Clean up unused pages code 1/2

See merge request https://gitlab.com/gitlab-org/gitlab/-/merge_requests/183013



Merged-by: Terri Chu <tchu@gitlab.com>
Approved-by: Jeff Park <jpark@gitlab.com>
Approved-by: Carla Drago <cdrago@gitlab.com>
Approved-by: Erick Bajao <fbajao@gitlab.com>
Approved-by: Terri Chu <tchu@gitlab.com>
Co-authored-by: janis <jaltherr@gitlab.com>