GitLab Version Check - UI Documentation

Why is this change being made?

Closes gitlab-org/gitlab#387878 (closed)
Set up for gitlab-org/gitlab#387879 (closed)

This is an effort to document the GitLab Version Check UI Suite that we have been working on over the past year. There have been some confusions as we've continued to expand this feature. I started to document the UI on this issue: gitlab-org/gitlab#387719 (closed). I think having these details in our handbook would provide a lot of value. Additionally in the information in the existing doc is a bit outdated to how the feature works now.

Author Checklist

• Provided a concise title for this Merge Request (MR)
• Added a description to this MR explaining the reasons for the proposed change, per say why, not just what
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  • If this is a change that directly impacts the majority of global team members, it should be a candidate for #company-fyi. Please work with internal communications and check the handbook for examples.

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