Add support for keyring authentication

[clement-chaneching]

Hello,

It would be nice if this action could support keyring authentication for Google Artifact Registries:

This runs, but it could be cleaner with the setup pixi action:

      - id: auth
        name: Authenticate to Google Cloud
        uses: google-github-actions/auth@v2
        with:
          workload_identity_provider: ${{secrets.WORKLOAD_IDENTITY_PROVIDER}}
          service_account: ${{inputs.SERVICE_ACCOUNT}}
          token_format: access_token

      - name: Run Tests
        run: |
          curl -fsSL https://pixi.sh/install.sh | bash
          export PATH=/home/runner/.pixi/bin:$PATH
          pixi global install pipx
          pipx install keyring
          pipx inject keyring keyrings.google-artifactregistry-auth --index-url https://pypi.org/simple
          pixi install --environment test --pypi-keyring-provider subprocess
          pixi run --environment test tests

Thanks!

[eightysteele]

Confirming that the workaround works and that it would certainly be a nicer devx via the pixi action. :)