[nfc] fix typo applications/Chat/coati/

[digger-yu]

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📝 What does this PR do?

fix typo applications/Chat/coati/
modified: applications/Chat/coati/ray/experience_maker_holder.py
modified: applications/Chat/coati/ray/lora_constructor.py
modified: applications/Chat/coati/trainer/strategies/colossalai.py
Make code easier to read

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