misc/py-shell-gpt: update to 0.8.3

Upstream removed the test files from the distribution. So temporarily
disable test target.

Changelog:

• https://github.com/TheR1D/shell_gpt/releases/tag/0.8.2
• https://github.com/TheR1D/shell_gpt/releases/tag/0.8.3

PR: 270542
Reported by: John Hein <jcfyecrayz@liamekaens.com>