Is it possible to include a custom message in the workflow notifications?

[dmirica-gpsw]

We have Github actions jobs that run tests and the report is uploaded to a web server.
It would help us a lot if in the workflow notifications/thread we could include the url to the report which is generated at runtime (eg https://server/reports/runName-runNumber/index.html).
This would help us as we don't need to open the run anymore and we can go to the report directly from slack