[Feature/Idea]: remove dead versions: check for existing PRs

[a-mnich]

What would you like to see changed/added?

I'm currenty maintaining a few packages where the downloads for old versions get withdrawn after some time.
I am currently using a self-scripted, less advanced solution to remove the dead versions.

The komac remove dead versions command seems to be very practical for this, but it would be good if a check that searches for already open PRs could be implemented for the '--auto' argument to reduce the possibility of opening duplicate PRs.
(I think the update command has also implemented simillar behaviour)
With this it would be easily possible to run the command on a scheduled basis in a CI/CD pipeline.