Group identical code quality issues in MR widget by file

This is an actionable insight from the UX Department: MRs experience async critique research ([insight][insight]).

What

In the merge request widget for code quality, there is a lot of item duplication. There is no information hierarchy or typography differences.

Why

With so much duplicated content, it's difficult to focus on what makes each issue different. It also makes it hard to ignore a specific group of similar/identical issues.

How

Items should be sorted by severity and then grouped by category so that it's easier to parse the list for common issues that can be resolved.