Merge multiple Dockerfiles into a single one

[SimonYansenZhao]

Description

This PR merges the following multiple uses of Dockerfile into a single place in tools/docker/Dockerfile for easier maintainance in the future:

• Dev container in .devcontainer/devcontainer.json for development
• AML testing environment in tests/ci/azureml_tests/aml_utils.py for testing
• Dockerfile in tools/docker/Dockerfile for general users

Related Issues

None

References

• Developing inside a Container via VS Code
• Create Azure Machine Learning Custom Environment
• Recommenders Docker Support

Checklist:

• I have followed the contribution guidelines and code style for this project.
• I have added tests covering my contributions.
• I have updated the documentation accordingly.
• I have signed the commits, e.g. git commit -s -m "your commit message".
• This PR is being made to staging branch AND NOT TO main branch.

[miguelgfierro]

hi @SimonYansenZhao the tests should be working now after #2169

[miguelgfierro]

LGTM

[miguelgfierro]

Looks great.

Fixed some minor typos