Save Test Results to File or Action Output

Would it be possible to have an option to save the test results to a file instead of posting a job summary? My use case is I am using the `parallel: true` flag to run across multiple runners and I want to combine the test results into one post per `group:` instead of each parallel run having their own. The easiest way I can think to accomplish this is to save what would normally put to the job summary into a file (json, csv, etc) and upload those as artifacts. Then I can have a job that waits for all the parallel jobs to complete, aggregates the results, and posts a single summary.

If that's not possible, I could create such a file myself if the various fields such as `testResults.totalPassed` were exposed as action outputs.