Add dockerfile for python 3.8, cuda 11.8 and torch 2.0.1 version

[dongwon00kim]

in "runtime/python/Dockerfile" using python 3.8 is not the same version as the training environment in README.md. So I add dockerfile for python 3.8, cuda 11.8, torch 2.0.1 using miniconda as default.

docker build -t cosyvoice:latest -f docker/Dockerfile .

docker run --rm cosyvoice:latest python --version 
docker run --rm cosyvoice:latest pip show torch