Add reference to open-interpreter-termux in README

[MikeBirdTech]

Describe the changes you have made:

Added Android section to readme that links to https://github.com/Arrendy/open-interpreter-termux

Reference any relevant issues (e.g. "Fixes #000"):

Pre-Submission Checklist (optional but appreciated):

• [ ] I have included relevant documentation updates (stored in /docs)
• [x] I have read docs/CONTRIBUTING.md
• [x] I have read docs/ROADMAP.md

OS Tests (optional but appreciated):

• [ ] Tested on Windows
• [ ] Tested on MacOS
• [ ] Tested on Linux