CI: move check_docs_links to gitlab-org tag

What does this MR do?

CI: move check_docs_links to gitlab-org tag

Move runner tags for check_docs_links to gitlab-org, which is present on GitLab.com and Dev.

Change the CI job tags for check_docs_links job to gitlab-org, for the sake of confirmation. Consider, in the future, removing this job from Dev entirely. gitlab-org may not be the best tag! We do want this to run for a fork as well!

Stems from a recent Docs CI MR.

Applies the same fix as applied in Charts: gitlab-org/charts/gitlab!3024 (merged)

Related issues

Closes #1123 (closed)

Closes #1125 (closed)

Checklist

See Definition of done.

For anything in this list which will not be completed, please provide a reason in the MR discussion.

Required

• Merge Request Title and Description are up to date, accurate, and descriptive
• MR targeting the appropriate branch
• MR has a green pipeline on GitLab.com
• When ready for review, MR is labeled "~workflow::ready for review" per the Distribution MR workflow

Expected (please provide an explanation if not completing)

• Test plan indicating conditions for success has been posted and passes
• Documentation created/updated
• Tests added
• Integration tests added to GitLab QA
• Equivalent MR/issue for omnibus-gitlab opened
• Validate potential values for new configuration settings. Formats such as integer 10, duration 10s, URI scheme://user:passwd@host:port may require quotation or other special handling when rendered in a template and written to a configuration file.