Handling multiple secrets in build-secrets #72

I'm looking to add multiple secrets to my Astronomer deploy step. The documentation seems to only specify a single parameter being allowed. It would be useful to be able to provide more than one secret if, for example, you're passing in a username and password as a secret:

        uses: astronomer/deploy-action@v0.6
        with:
          deployment-id: *****
          description: ${{ github.sha }}
          build-secrets: id=PLATFORM_USERNAME,env=${{ secrets.PLATFORM_USERNAME }}, id=PLATFORM_PASSWORD,env=${{ secrets.PLATFORM_PASSWORD }}

Can someone clarify if this is currently supported? If so, how can this be achieved?