checkout commits fails during bisect

### Describe the bug
I've found that during bisects, lazygit would not let me manually (using lazygit) check out different commits, instead leaving me at the automatically-determined one.

### To Reproduce
Steps to reproduce the behavior:

1. start a bisect, picking good and bad commits
2. try checking out a different commit within the range
3. find you're still at the automatically selected one

### Expected behavior
check-out still works

### Screenshots
-

### Version info:

* `lazygit --version`: `commit=, build date=, build source=nix, version=0.56.0, os=linux, arch=amd64, git version=2.51.2`
* `git --version`: `git version 2.51.2`

### Additional context
a use-case i found for this is a case where i knew failures to be significantly faster to evaluate than succeeding commits, leading me to manually prefer failing over succeeding commits in my bisect such as to stray from 'least commits evaluated' to instead minimize time to bisect completion.