Workdir not saved when it contains the games executable

[Lucki]

Changing the working directory to any other folder than the folder with the executable in it gets saved but when the folder contains the executable closing the dialog empties the input field.

Verifying with a custom script containing pwd the workdir defaults to the home directory instead of the executable path.

Probably a side issue of this is that the GH_INSTALL_DIR variable passed to custom scripts is empty/missing and any following variables are shifted -1.

Expected behavior

The workdir defaults to the executable path or the input field doesn't get cleared.

Actual behavior

The workdir defaults to the home directory.

Steps to reproduce

1. Set up a game which needs to be executed in a specific working dir.
2. Change the working directory to any directory, notice it gets saved when closing and reopening the game property dialog.
3. Change the working directory back to the path containing the executable, notice the path doesn't get saved. (use case: overlays merge directory)

Version and environment

- GameHub
    Version: 0.15.0-6d20061-makepkg
    Branch:  makepkg
    Commit:  6d200618bb16a16cab849767d7381584f7ff440f
- Environment
    Distro:  Arch Linux
    DE:      GNOME
    GTK:     3.24.14
    Themes:  Numix-ArchBlue | Numix-Circle