Submit upstream the disclaimer system for Contribute sections of docs site

Relevant work had been completed here: MVC to hide "Contribute" pages and navigation i... (#203 - closed)

Here's the list of MRs that needs to be submitted:

GitLab Docs: https://gitlab.com/gitlab-com/localization/tech-docs-forked-projects/test/gitlab-docs/-/merge_requests/28

Other Translation MRs (that gets automatically pushed when we push translations upstrea)