Adjust Git Status Parsing to Better Handle Null Chars

### Description Fixes an issue with git status parsing where the substring indexing was off-by-one when creating the file string due to an index being incremented before creating a substring. Fixes this by incrementing the current string index *after* returning the correct substring. The related issue is marked as a Tahoe bug, the Tahoe bug is that Tahoe now shows the null character as a %00 at the end of the label, where previous macOS versions did not. This change is retroactive however as it is a bug fix. ### Related Issues * closes #2119 ### Checklist - [x] I read and understood the [contributing guide](https://github.com/CodeEditApp/CodeEdit/blob/main/CONTRIBUTING.md) as well as the [code of conduct](https://github.com/CodeEditApp/CodeEdit/blob/main/CODE_OF_CONDUCT.md) - [x] The issues this PR addresses are related to each other - [x] My changes generate no new warnings - [x] My code builds and runs on my machine - [x] My changes are all related to the related issue above - [x] I documented my code ### Screenshots N/A