Update dockerfile

[RunningLeon]

Motivation

some problems while installing lmdeploy in the docker container

• python3 -m pip install -e :
  • fails to install lmdeploy in editable mode as in issue 不能pip install -e #790
  • lmdeploy cli is unaccessible as lmdeploy package is not installed.
• python3 -m pip install --user -e :
  • can successfully install lmdeploy in editable mode, but lmdeploy cli in not installed.

Modification

• Use venv to fix installing lmdeploy in editable mode in docker containers
• Upgrade torch to torch2.1.0+cu118 as pytorch-poc requires.
• add __main__.py to enable using cli like python3 -m lmdeploy list.

BC-breaking (Optional)

Does the modification introduce changes that break the backward-compatibility of the downstream repositories?
If so, please describe how it breaks the compatibility and how the downstream projects should modify their code to keep compatibility with this PR.

Use cases (Optional)

If this PR introduces a new feature, it is better to list some use cases here, and update the documentation.

Checklist

1. Pre-commit or other linting tools are used to fix the potential lint issues.
2. The modification is covered by complete unit tests. If not, please add more unit tests to ensure the correctness.
3. If the modification has a dependency on downstream projects of a newer version, this PR should be tested with all supported versions of downstream projects.
4. The documentation has been modified accordingly, like docstring or example tutorials.

[RunningLeon]

An example building log is here:
https://github.com/RunningLeon/lmdeploy/actions/runs/7334739555