Update Docker file from Ubuntu 20.04 to Ubuntu 22.04.

contrib/Dockerfile

@@ -15,7 +15,9 @@
 
 # Docker image used for running tests the under all the supported Python
 # versions
-FROM ubuntu:20.04
+FROM ubuntu:22.04
+
+ARG DEBIAN_FRONTEND=noninteractive
 
 RUN set -e && \
     apt-get update && \
@@ -32,18 +34,19 @@ RUN set -e && \
       python3.9 \
       python3.10 \
       python3.11 \
-      python-dev \
+      python3-dev \
       python3.7-dev \
       python3.8-dev \
       python3.9-dev \
       python3.10-dev \
       python3.11-dev \
-      python3.6-distutils \
       python3.7-distutils \
       python3.8-distutils \
+      python3.9-distutils \
       pypy3 \
       pypy3-dev \
       python3-pip \
+      python3-distutils \
       libvirt-dev \
       # Needed by libvirt driver
       pkg-config \
@@ -53,13 +56,13 @@ RUN set -e && \
 # Workaround for zipp import error issue - https://github.com/pypa/virtualenv/issues/1630
 RUN python3.8 -m pip install --upgrade pip
 
-RUN set -e && \
-    python3.8 -m pip install --no-cache-dir "tox==4.4.2"
-
 COPY . /libcloud
 
 RUN if [ ! -f "/libcloud/README.rst" ]; then echo "libcloud/README.rst file not found, you are likely not running docker build from the repository root directory"; exit 1; fi
 
 WORKDIR /libcloud
 
+RUN set -e && \
+    python3.8 -m pip install --no-cache-dir -r requirements-ci.txt
+
 CMD ["tox", "-e", "lint,isort-check,black-check,bandit,py3.7,py3.8,py3.9,py3.10,py3.11,pypypy3.8"]