`sync-pr-commit-title` - Broken on new merge box

### Description

Part of this but it's an important feature so I'm giving it its own issue

- #8123 

### How to replicate the issue + URL

Any open PR you can merge, like https://github.com/refined-github/sandbox/pull/114

### Extension version

25.5.18

### Browser(s) used

Safari

### Token ⚠️

- [x] I set a token in the options page. I understand that some features require a token to work.