Fix maisi diffusion net single gpu training issue

[KumoLiu]

Fix maisi diffusion net single gpu training issue

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• Avoid including large-size files in the PR.
• Clean up long text outputs from code cells in the notebook.
• For security purposes, please check the contents and remove any sensitive info such as user names and private key.
• Ensure (1) hyperlinks and markdown anchors are working (2) use relative paths for tutorial repo files (3) put figure and graphs in the ./figure folder
• Notebook runs automatically ./runner.sh -t <path to .ipynb file>

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[mingxin-zheng]

Thanks @KumoLiu . The change looks good to me.

If you have a chance, can you also update the type hint (int) in here:

tutorials/generation/maisi/scripts/diff_model_setting.py

Line 77 in 97b107b

def initialize_distributed(num_gpus) -> tuple:

[KumoLiu]

Hi @dongyang0122, @guopengf and @Can-Zhao, I will merge this PR for qa test first. If you have any further comments, we can update it in the later PRs, thanks.