message: Simplify Debian 10 setup
diff: -FROM debian:buster
  +FROM debian:10
  RUN apt update -y && \
  apt upgrade -y
  RUN apt install -y \
  cmake \
  - g++-8 \
  + g++ \
  git \
  libssl-dev \
  make \
  && apt autoclean
  -
  -ENV CXX=/usr/bin/g++-8
  