Overly verbose comments in JIRA

Zendesk issue: https://gitlab.zendesk.com/agent/tickets/29677

JIRA ends up getting a lot of comments added based on certain mentions and actions in GitLab. In some cases this is overly verbose. This is probably more related to our global issue mentioning system than JIRA specifically, but this is the example we have.

Here's a summary of the comments that appear in the screenshot:

1. A mention in the commit message itself.
2. A mention in the merge request description.
3. The issue was transitioned because it was mentioned with the issue closing pattern in the commit itself. When that commit goes to the default branch (master), the JIRA issue is closed.
4. Since the issue closing pattern was also present in the merge request description, it is copied to the merge commit message. This causes another transition comment.
5. A mention in the merge commit, related to #4 (closed).

1 and 2 will be hard to eliminate because they are distinct and one can exist without the other. Again 3 and 4 will probably be hard to eliminate because they are distinct and one can exist without the other. 5 can maybe be eliminated because we know that the transition occurred on the same commit.

Is there any way we can clean this up a bit and avoid multiple comments?

cc/ @DouweM You probably know a lot about the reference system.