www/tgpt: Update 2.9.2 → 2.9.3

• Added Gemini provider.
• Fix missing letters in response.
• Images generated with same prompt will be random.

Port changes:

• Added new provider Gemini to pkg-descr.

ChangeLog:
https://github.com/aandrew-me/tgpt/releases/tag/v2.9.3

PR: 285880
Reported by: portscout