[CI] Publish to PyPI upon Tag

[benjaminye]

This PR introduces CI pipeline for PyPI. Addresses #114, #106.

What does this PR do?

• Establish git tags as single source of truth for package releases and versioning

• Workflow is triggered when

  • using Github web UI to tag and publish a new release
    
  • using Github CLI to publish a new release
    • e.g. gh release create --repo seanh/gha-python-packaging-demo --generate-notes 0.0.1

• Dynamic versioning and version convention (Semver) enforcement via poetry plugin

  • Version specified by tag will be replacing values found within pyproject.toml as well as in any __init__.py files (i.e. where we do __version__='0.0.0').

Requirement

• @truskovskiyk or @RohitSaha, please add a github repo secret PYPI_API_TOKEN with a (preferably) scoped PyPI API Token.

[truskovskiyk]

@benjaminye we don't have the right to add secrets, so this is going to be blocked for now

[benjaminye]

@benjaminye we don't have the right to add secrets, so this is going to be blocked for now

@truskovskiyk, I can add repo-scoped secrets for this repo that I created: https://github.com/georgian-io/cohere-rerank-eval.

Seems like you need to be the owner of the repo to be able to do this. @RohitSaha please confirm if this guide works for you: https://docs.github.com/en/actions/security-guides/using-secrets-in-github-actions#creating-secrets-for-a-repository

[benjaminye]

@truskovskiyk

Forked the repo and tested the pypi publish workflow on testPyPI. It's working as desired.