[Model] Added Google T5 model support to vLLM

[bmullick-amd]

This PR adds t5 model integration scripts to add support for this model in vLLM repository.
I have tested the results locally both in Nvidia H100 gpus as well as MI300X GPUs using rocm/vllm repository.

[github-actions]

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[DarkLight1337]

Thanks for implementing this!

cc @afeldman-nm

It looks like this implementation doesn't use the custom attention bias (relative_attention_bias), as described in #7366 (comment). Do you have plans to add support in this PR or future PRs?