Show `pr-base-commit` on more PRs

### Description

I think we can add the link in the same area, but this was not done in the original PR: 

- https://github.com/refined-github/refined-github/pull/6538

<img width="716" alt="Screenshot 24" src="https://user-images.githubusercontent.com/1402241/232437502-a660ed97-655b-4cbd-b96b-ba412f883c41.png">


### Example URLs

https://github.com/refined-github/sandbox/pull/9