fix: unable to find output_dir in multi-GPU during resume_from_checkpoint check

[Abhishek-TAMU]

Description of the change

Addition of code to create output_dir in accelerate_launch.py if it doesn't exist.

Related issue number

#1352

How to verify the PR

Run full fine tuning or LoRA tuning with multiple GPUs and check if issue exists.

Was the PR tested

• [ ] I have added >=1 unit test(s) for every new method I have added.
• [x] I have ensured all unit tests pass

[github-actions[bot]]

Thanks for making a pull request! 😃 One of the maintainers will review and advise on the next steps.

[github-actions[bot]]

Thanks for making a pull request! 😃 One of the maintainers will review and advise on the next steps.