Spurious n gets appended as prefix to name of file before opening it

A spurious n gets appended as prefix to the file name before opening it, hence not really opens the intended file.

This does not happen from all directories. It happens in a git directory I have on my system: ``~/Desktop/textfiles/grid-typesetting/``. All important files worked upon in the video below are in that directory:

https://user-images.githubusercontent.com/25681815/120881923-5f00a000-c589-11eb-989b-f94e25f99366.mp4

Nvim (same problem also occurs on latest vim):
```
NVIM v0.5.0-dev+nightly-298-g0a653f7ab
Build type: Release
LuaJIT 2.1.0-beta3
```
System:
```
macOS BigSur 11.4 ARM64 (Apple M1 chip)
```
Terminal (didn't try on other terminals):
```
iTerm2 (3.4.8. i.e. latest)
```

Reproduce the issue in vim-tree using ~/Desktop/textfiles/grid-typesetting/ and the provided macOS, ARM64, iTerm2, Neovim, and Vim context. Start by tracing the file-opening path used when the spurious “n” is added, then verify that the intended file opens without the prefix in both Vim and Neovim.

Written by the indexing model from the issue text.