util: Cleanup the provision_root.sh

Change-Id: I58215dddc34476695c7aedc77b55d338e0304198

util/github-runners-vagrant/provision_root.sh

@@ -5,9 +5,9 @@ set -eu -o pipefail # -x: is for debugging
 
 apt-get update
 apt-get upgrade -y
-apt-get install -y software-properties-common
 add-apt-repository --yes --update ppa:git-core/ppa
 apt-get install -y \
+  software-properties-common \
   bash \
   build-essential \
   clang-format \
@@ -25,8 +25,12 @@ apt-get install -y \
   tree \
   wget \
   yamllint \
-  zstd
-snap install jq
+  zstd \
+  jq \
+  apt-transport-https ca-certificates \
+  curl \
+  gnupg \
+  lsb-release
 
 # Install docker
 apt-get install -y apt-transport-https ca-certificates curl gnupg lsb-release
@@ -34,10 +38,11 @@ curl -fsSL https://download.docker.com/linux/ubuntu/gpg | gpg --dearmor -o /usr/
 echo "deb [arch=amd64 signed-by=/usr/share/keyrings/docker-archive-keyring.gpg] https://download.docker.com/linux/ubuntu $(lsb_release -cs) stable" | tee /etc/apt/sources.list.d/docker.list > /dev/null
 apt-get update -y
 apt-get install -y docker-ce docker-ce-cli containerd.io
-groupadd docker || true
-gpasswd -a vagrant docker
-newgrp docker
-systemctl restart docker
+
+# Add the Vagrant user to the docker group.
+# Note: The VM needs rebooted for this to take effect. `newgrp docker` doesn't
+# work.
+usermod -aG docker vagrant
 
 # Cleanup
 apt-get autoremove -y