Disable unattended upgrades

Related-Prod: PRODX-3456
Change-Id: I4de44d43f491abb2771fdf5ae3b3a019728f75bc
diff --git a/de/heat-templates/scripts/instance_boot.sh b/de/heat-templates/scripts/instance_boot.sh
index e4b6485..859f182 100644
--- a/de/heat-templates/scripts/instance_boot.sh
+++ b/de/heat-templates/scripts/instance_boot.sh
@@ -116,6 +116,9 @@
 }
 
 function install_required_packages {
+    # Disable unattended upgrades
+    sed -i 's/1/0/' /etc/apt/apt.conf.d/20auto-upgrades
+
     function install_retry {
         apt update
         export DEBIAN_FRONTEND=noninteractive; apt install -y apt-transport-https ca-certificates curl software-properties-common jq unzip atop iptables-persistent socat