Improve Related Merge Requests
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### Proposal
When a MR with a commit that references an issue is merged the referenced MR is not listed in the "Related merge requests" section of the issue. If the MR text itself doesn't have a reference, it doesn't show up in the "Related merge requests" section.
This proposal is to make relating an MR automatic if it is mentioned in a commit or to create an option to enable or disable it as the default behavior.
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