hdajackretask doesn't check for script's exit code

[GitHub issues - edited]

alsa-project/alsa-tools issue #8 was edited from kroq-gar78:

`hdajackretask` creates a script in `/tmp` before executing it. When `/tmp` is mounted with `noexec`, running that script will fail, but the GUI gives no indication that it failed.

I'm on Ubuntu 18.04.5 with `alsa-tools-gui` package version `1.1.3-1`.

The GUI should check for the exit code of the script, and notify the user appropriately if the script failed to execute.

Also, if this isn't the appropriate place to report a bug, please let me know!

Issue URL     : https://github.com/alsa-project/alsa-tools/issues/8
Repository URL: https://github.com/alsa-project/alsa-tools