Fix default variable issue.

[tyfiero]

Describe the changes you have made:

idk when it happened, but something broke in the last few days, where 'default' is not defined. This prevents poetry run interpreter from running at all. Here is the error:

~/Documents/open-interpreter $ poetry run interpreter
Traceback (most recent call last):
  File "<string>", line 1, in <module>
  File "/Users/tyfiero/Documents/open-interpreter/interpreter/terminal_interface/start_terminal_interface.py", line 442, in main
    start_terminal_interface(interpreter)
  File "/Users/tyfiero/Documents/open-interpreter/interpreter/terminal_interface/start_terminal_interface.py", line 288, in start_terminal_interface
    default=default,
            ^^^^^^^

I added back in default = arg.get("default") to fix this issue.

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
• [x] Tested on MacOS
• [ ] Tested on Linux