[docker] Use python3 as a base image in docker file
#----------------------------- BUILD STAGE ------------------------------#
###############################################################################
-FROM python:2.7.16-slim-stretch as builder
+FROM python:3.6-slim-stretch as builder
ARG CC_VERSION=master
ENV CC_VERSION ${CC_VERSION}
@@ -33,7 +33,7 @@ RUN find www/scripts/plugins/dojo/ -name *.uncompressed.js -exec rm -rf '{}' \;
#-------------------------- PRODUCTION STAGE ----------------------------#
###############################################################################
-FROM python:2.7.16-slim-stretch
+FROM python:3.6-slim-stretch
ARG CC_GID=950
ARG CC_UID=950
