Multi-platform docker images pushed to DockerHub

[docktermj]

See Senzing/senzingapi-runtime#59

[docktermj]

Although the implementation is in place (https://github.com/Senzing/senzingapi-tools/blob/main/.github/workflows/docker-push-containers-to-dockerhub.yaml) the final configuration is still needed.

      - name: Docker build images
        run: |
          docker buildx build \
            --no-cache \
            --platform linux/amd64 \
            --push \
            --tag senzing/sengingapi-tools \
            --tag senzing/senzingapi-tools:${{ github.ref_name }} \
            .

[docktermj]

Replaced by senzing-factory/github-action-docker-buildx-build#9