change docker image to a ubuntu base

.docker/Dockerfile

-FROM debian:latest
-RUN apt-get update && \
-	 apt-get install \
-	 curl \
-	 python3 \
+# Use docker as parent image
+FROM ubuntu:20.04
+
+# http://bugs.python.org/issue19846
+ENV LANG C.UTF-8
+
+# install dependencies
+RUN apt-get update && DEBIAN_FRONTEND=noninteractive apt-get install -y \
+  acl \
+  docker.io \
   python3-pip \
-	 python3-requests \
-	 python3-pandas \
-	 python3-html2text \
-     tox \
+  python3.6 \
+  python3.7 \
+  python3.8 \
+  python3-dev \
+  gcc \
+  make \
   git \
-	 openjdk-11-jdk-headless \
-	 python-autopep8 \
-     python3-pytest \
+  bash \
+  curl \
+  gettext \
+  python3-requests \
+  python3-packaging\
+  libffi-dev \
+  #openssl-dev \
+  libc-dev \
+  libxslt1.1 \
+  libxslt-dev \
   libxml2 \
-	 -y
+  libxml2-dev \
+  openjdk-14-jre-headless \
+  openssl
+
+RUN pip3 install docker-compose==1.25 pytest-shell
+
+RUN mkdir -p /opt/caosdb/build_docker/
+
 COPY .docker/wait-for-it.sh /wait-for-it.sh
 ADD https://gitlab.com/api/v4/projects/13656973/repository/branches/master \
    pylib_version.json