message: New PPA repo added
diff: FROM ubuntu:18.04
  -RUN apt-get update
  +RUN apt-get update; \
  + apt install -y software-properties-common; \
  + add-apt-repository ppa:ubuntu-toolchain-r/test
  #Install iroha
  COPY iroha.deb /tmp/iroha.deb
  -RUN apt-get install -y /tmp/iroha.deb; \
  - rm -f /tmp/iroha.deb
  +RUN set -e; apt-get install -y /tmp/iroha.deb; \
  + rm -f /tmp/iroha.deb; \
  + apt-get -y clean && \
  + rm -rf /var/lib/apt/lists/*
  WORKDIR /opt/iroha_data
  