Link to post-merge review/audit from commit details
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## Problem to solve
When following a post-merge review workflow, or a workflow where changes are simply pushed and then audited at a later date, I want to know which commits have been reviewed or audited.
## Intended users
Software Developer
Development Team Lead
## Further details
We'd like to use comments on commits for code-review, but it's really hard to track which commits have been reviewed and which ones not.
We don't want to require the use of merge-requests for code reviews, it should possible to review code on smaller commits in an ad-hoc fashion and easily visualize that.
## Proposal
If post-merge reviews are implemented as a first party concept, reviews/audits should be cross linked from commits in the same way that merge requests are cross linked from commits.
<details><summary>Original proposal</summary>
Commit comments can already reference Labels through the `~label` notation.
If those labels would simply be displayed in the commit log page (`https://gitlab.com/group/page/commits`) and at the top of each commit page, we could instantly see which commits have been reviewed through the `~Reviewed` label and which ones are not.
This would also open up other ways of tracking work needed on commits by leveraging the already existing label infrastructure.
When a comment on a commit has had a label added, that label should appear on the commits history page and the dedicated commit page.
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## Links / references
issue