use apt to install azure cli rather than pip

images/capi/Dockerfile

@@ -18,6 +18,9 @@ ARG BASE_IMAGE=docker.io/library/ubuntu:focal
 FROM $BASE_IMAGE
 
 RUN apt-get update && apt-get install -y apt-transport-https ca-certificates python3-pip curl wget git rsync vim unzip build-essential \
+    && curl -sL https://packages.microsoft.com/keys/microsoft.asc | gpg --dearmor | tee /etc/apt/trusted.gpg.d/microsoft.gpg > /dev/null \
+    && echo "deb [arch=amd64] https://packages.microsoft.com/repos/azure-cli/ focal main" | tee /etc/apt/sources.list.d/azure-cli.list \
+    && DEBIAN_FRONTEND="noninteractive" apt-get update && apt-get install -y azure-cli \
     && useradd -ms /bin/bash imagebuilder \
     && apt-get purge --auto-remove -y \
     && rm -rf /var/lib/apt/lists/*

images/capi/hack/ensure-azure-cli.sh

@@ -22,14 +22,15 @@ set -o pipefail
 
 source hack/utils.sh
 
-_version="2.9.0"
-
 # Change directories to the parent directory of the one in which this
 # script is located.
 cd "$(dirname "${BASH_SOURCE[0]}")/.."
 
 if command -v az >/dev/null 2>&1; then exit 0; fi
 
-ensure_py3
-pip3 install --user "azure-cli==${_version}"
-ensure_py3_bin az azure-cli
+echo "installing Azure CLI"
+apt-get update && apt-get install -y ca-certificates curl apt-transport-https lsb-release gnupg
+curl -sL https://packages.microsoft.com/keys/microsoft.asc | gpg --dearmor | tee /etc/apt/trusted.gpg.d/microsoft.gpg > /dev/null
+AZ_REPO=$(lsb_release -cs)
+echo "deb [arch=amd64] https://packages.microsoft.com/repos/azure-cli/ ${AZ_REPO} main" | tee /etc/apt/sources.list.d/azure-cli.list
+apt-get update && apt-get install -y azure-cli