Detects modifications with submodules where there are none

**Describe the bug**
I have several submodules in my project. For some submodules, `gitui` keeps listing "M" modifications. When looking at the change, it shows: `size: 0 B -> 0 B (+0 B)`. When I check with `git status`, there is nothing listed as modified.

Also, when I check the Submodules in `gitui`, all the submodules that are listed as modified have the following info:

> Commit:
0000000000000000000000000000000000000000

This contradicts the information shown in the list where the correct hash is displayed (see screenshot below).

When I try to stage these phantom-modifications, I get this error:
>Error
staging error:
git error:repository path '' is not owned by current user; class=Config (7); code=Owner (-36)

**Screenshots**


**Context (please complete the following information):**
- OS/Distro + Version: Linux (WSL), Windows
- GitUI Version:
- Linux: `nightly 2025-01-21 ()`
- Windows: `0.27.0 2025-01-14 (99f6967)`
- Rust version: `1.85.1`

No se nombran archivos fuente, pruebas ni puntos de entrada. Empieza reproduciendo las modificaciones fantasma de los submódulos en las configuraciones de WSL o Windows indicadas y compara la vista Submodules de gitui con git status. Se considera terminado cuando los submódulos limpios ya no aparecen como modificados y el staging ya no provoca el error de ownership indicado.

Escrito por el modelo de indexación a partir del texto del issue.