Show head lines of commits in the issue view
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### Background
Currently, when a commit mentions a GitLab issue (`Refs #xxxx`) on the respective issue page (https://gitlab.com/zzzzzzz/-/issues/xxxx) is displayed as
```
John Doe mentioned in commit yyyyy@737430e3 4 days ago
John Doe mentioned in commit yyyyy@466a0410 4 days ago
John Doe mentioned in commit yyyyy@eb3e9051 4 days ago
John Doe mentioned in commit yyyyy@48f26921 3 days ago
```
If a commit mentions a GitLab issue as `Fixed #xxxx`, then the commit is not mentioned at all. It just shows a closure notice without even a link to the commit:
```
John Doe closed 3 days ago
```
### Proposal
For all commits that mention an issue, regardless of if it's `Refs`, `Fixes` or anything else, the commit headline should be displayed:
```
John Doe mentioned in commit "Data structures for implementing feature A" 4 days ago
John Doe mentioned in commit "Backend support for feature A" 4 days ago
John Doe mentioned in commit "Frontend support for feature A" 4 days ago
John Doe mentioned in commit "Enable feature A in staging" 3 days ago
```
The closure commit could be displayed as
```
John Doe closed the issue with commit "Enable feature A in production" 3 days ago
```
Why is it important? Currently, if a user is looking for a specific commit related to an issue, they have to open each of the referencing commits. It's a big inconvenience and waste of time.
This feature should be easy to implement, but significantly improve usability of the product.
issue