fix datalab_pip.yml to upload only once

[iglesu]

Break it in two jobs, one that builds all the python versions and the other one that just uploads once.

maybe set a job-level output say package-dir i.e.
jobs:
build:
runs-on: ubuntu-latest
strategy:
matrix:
python-version: ['3.9', '3.10', '3.11']
outputs:
package-dir: ${{ steps.build.outputs.package-dir }}

and then in the upload job:

• name: Upload package to PyPI
  env:
  TWINE_USERNAME: token
  TWINE_PASSWORD: ${{ secrets.PYPI_TOKEN }}
  PYPI_REPO_URL: ''
  run: |
  if [ -z "${{ env.PYPI_REPO_URL }}" ]; then
  twine upload --verbose ${{ needs.build.outputs.package-dir }}/*
  else
  twine upload --verbose --repository-url "${{ env.PYPI_REPO_URL }}" ${{ needs.build.outputs.package-dir }}/*
  fi

  or something like that