Desktop offers and tries to create a fork even if forking is disabled

### The problem

Working on a private repo with readonly permissions surprisingly suggests forking:

YOLO-style, trying that:

...expectedly fails because forking is disabled:

Following the suggested link to the web, where the tooltip clearly states that forking is disabled:

### Release version

3.5.8 (arm64) (=current latest, https://github.com/desktop/desktop/releases/tag/release-3.5.8 )

### Operating system

MacOS Tahoe 26.5 (25F71)

### Steps to reproduce the behavior

1. Clone some private repository with readonly user permissions and disabled forking
2. Change some files in local clone of that repository
3. Open that local clone in Github desktop client
4. See the invalid suggestion to create the fork

### Log files

_No response_

### Screenshots

See above.

### Additional context

Tracking issue:
* https://github.com/desktop/desktop/issues/8509

No other issue mentions error message "The repository exists, but forking is disabled.": https://github.com/search?q=repo%3Adesktop%2Fdesktop+%22The+repository+exists%2C+but+forking+is+disabled%22&type=issues