Merge branch '415580-docs-git-protocol-ci-token' into 'master'

Update documentation re: git protocol restriction and CI_JOB_TOKEN

See merge request https://gitlab.com/gitlab-org/gitlab/-/merge_requests/143988



Merged-by: Jon Glassman <jglassman@gitlab.com>
Approved-by: Jon Glassman <jglassman@gitlab.com>
Co-authored-by: agius <andrew@atevans.com>