Pin prompt-toolkit>=3.0.43 to fix TypeError on Python 3.12

[ericholscher]

Summary

• Older versions of prompt-toolkit pass bare coroutines to asyncio.wait(), which raises TypeError on Python 3.12+ (coroutines were deprecated in 3.8, became an error in 3.12)
• prompt-toolkit is a transitive dependency via celery → click-repl
• Pins prompt-toolkit>=3.0.43 which wraps coroutines with ensure_future() before passing to asyncio.wait()

Error

File "prompt_toolkit/renderer.py", line 514, in wait_for_cpr_responses
    await wait(coroutines, return_when=FIRST_COMPLETED)
TypeError: Passing coroutines is forbidden, use tasks explicitly.

Test plan

• Verify celery starts without the TypeError on Python 3.12

[davidfischer]

I built the image and verified celery started and ran correctly with this change.