Fix publish with Python 3 (#27)

* Use Python2 image

Author: Denis-Averin

Dockerfile

@@ -2,7 +2,11 @@
 # docker build github.com/aspose-barcode-cloud/aspose-barcode-cloud-python -t barcode-cloud-python:$(git describe --tags)
 # docker run barcode-cloud-python:$(git describe --tags) publish -e "TEST_CONFIGURATION_ACCESS_TOKEN=" -e "TWINE_PASSWORD="
 
-FROM python:latest
+FROM python:2
+
+RUN apt-get update \
+	&& apt-get install -y python3-pip \
+	&& rm -rf /var/lib/apt/lists/*
 
 WORKDIR /aspose-barcode-cloud-python
 COPY . .

Makefile

@@ -40,7 +40,7 @@ publish: check_git test clean dist
 
 .PHONY: init-docker
 init-docker:
-	pip install -r publish-requirements.txt
+	python3 -m pip install -r publish-requirements.txt
 
 .PHONY: publish-docker
 publish-docker: init-docker test dist