Merge branch 'remove-lingering-new-project-readme-experiment-code' into 'master'

Remove lingering experiment code from new_project_readme_content

See merge request https://gitlab.com/gitlab-org/gitlab/-/merge_requests/138400



Merged-by: Alper Akgun <aakgun@gitlab.com>
Approved-by: Alper Akgun <aakgun@gitlab.com>
Co-authored-by: Doug Stull <dstull@gitlab.com>