Docker script update for Ubuntu 20.04

docker/ubuntu/bionic/base/Dockerfile

@@ -1,31 +0,0 @@
-ARG dist=ubuntu
-ARG tag=latest
-FROM ${dist}:${tag}
-
-MAINTAINER Sukchan Lee <acetcom@gmail.com>
-
-RUN apt-get update && \
-    apt-get upgrade -y && \
-    apt-get install -y --no-install-recommends \
-        python3-pip \
-        python3-setuptools \
-        python3-wheel \
-        ninja-build \
-        build-essential \
-        flex \
-        bison \
-        git \
-        libsctp-dev \
-        libgnutls28-dev \
-        libgcrypt-dev \
-        libssl-dev \
-        libidn11-dev \
-        libmongoc-dev \
-        libbson-dev \
-        libyaml-dev \
-        iproute2 \
-        ca-certificates \
-        netbase \
-        pkg-config && \
-    apt-get clean
-RUN python3 -m pip install meson