[Feature/Idea]: provide PR url as output

### What would you like to see changed/added?

It would be nice to have the generated PR URL as an output in the action. I would like this so I can set it as the url in an environment/deployment (https://dev.to/koseimori/how-to-set-dynamic-release-urls-in-environment-with-github-actions-l83)

I'm not familiar with komac, but it seems it should be possible to know which PR is created.