chore: limit transformers version

[yuki-97]

vllm<0.10.0 and transformers>=4.54.0 has a conflict which will cause the error below.
This PR limit transformers version to workaround it.

Error Log:

    raise ValueError(f"'{key}' is already used by a Transformers config, pick another name.")
ValueError: 'aimv2' is already used by a Transformers config, pick another name.

We could remove this limit once we upgrade vllm to >=0.10.0 since vllm-project/vllm#20921 fixed this.