Request: extend JUnit report

I've recently added the JUnit report to my (GitLab) CI pipeline. It works great, but I'd like for it to provide a bit more info on which exact test is which and what is failing (in case of a failure).

Current output:
```xml

```

I'd like to see the following additions:
- Include viewport label in testcase name
- Include selector in testcase name
- Include mis match percentage in failure & error message
- Include dimension difference in failure & error message

The output could then look something like:
```xml

```

I'd be happy to submit a PR for this if that would speed up things. I could also add configuration toggles for some/all of these changes if you'd like to keep the current default.