fix: 🐛 builder user remenants should not be present in node images

Currently the builder user is not deleted, just locked, which could pose
security risks for qemu, raw, nutanix and maas. So based on the
suggestions, cleaning up the user just like in the case of ova.

Author: sriramandev

images/capi/packer/maas/packer.json.tmpl

@@ -29,7 +29,7 @@
       "net_device": "virtio-net",
       "output_directory": "{{user `output_directory`}}",
       "qemu_binary": "{{user `qemu_binary`}}",
-      "shutdown_command": "echo '{{user `ssh_password`}}' | sudo -S -E sh -c 'usermod -L {{user `ssh_username`}} && {{user `shutdown_command`}}'",
+      "shutdown_command": "echo '{{user `ssh_password`}}' | sudo -S -E sh -c 'userdel -f -r {{user `ssh_username`}} && rm -f /etc/sudoers.d/{{user `ssh_username` }} && rm -f /etc/sudoers.d/90-cloud-init-users && {{user `shutdown_command`}}'",
       "ssh_password": "{{user `ssh_password`}}",
       "ssh_timeout": "2h",
       "ssh_username": "{{user `ssh_username`}}",

images/capi/packer/nutanix/packer.json.tmpl

@@ -16,7 +16,7 @@
       "nutanix_port": "{{user `nutanix_port`}}",
       "nutanix_username": "{{user `nutanix_username`}}",
       "os_type": "{{user `guest_os_type`}}",
-      "shutdown_command": "echo '{{user `ssh_password`}}' | sudo -S -E sh -c 'usermod -L {{user `ssh_username`}} && {{user `shutdown_command`}}'",
+      "shutdown_command": "echo '{{user `ssh_password`}}' | sudo -S -E sh -c 'userdel -f -r {{user `ssh_username`}} && rm -f /etc/sudoers.d/{{user `ssh_username` }} && rm -f /etc/sudoers.d/90-cloud-init-users && {{user `shutdown_command`}}'",
       "ssh_handshake_attempts": "100",
       "ssh_password": "{{user `ssh_password`}}",
       "ssh_timeout": "20m",

images/capi/packer/qemu/packer.json.tmpl

@@ -29,7 +29,7 @@
       "net_device": "virtio-net",
       "output_directory": "{{user `output_directory`}}",
       "qemu_binary": "{{user `qemu_binary`}}",
-      "shutdown_command": "echo '{{user `ssh_password`}}' | sudo -S -E sh -c 'usermod -L {{user `ssh_username`}} && {{user `shutdown_command`}}'",
+      "shutdown_command": "echo '{{user `ssh_password`}}' | sudo -S -E sh -c 'userdel -f -r {{user `ssh_username`}} && rm -f /etc/sudoers.d/{{user `ssh_username` }} && rm -f /etc/sudoers.d/90-cloud-init-users && {{user `shutdown_command`}}'",
       "ssh_password": "{{user `ssh_password`}}",
       "ssh_timeout": "2h",
       "ssh_username": "{{user `ssh_username`}}",

images/capi/packer/raw/packer.json.tmpl

@@ -30,7 +30,7 @@
           "virtio"
         ]
       ],
-      "shutdown_command": "echo '{{user `ssh_password`}}' | sudo -S -E sh -c 'usermod -L {{user `ssh_username`}} && {{user `shutdown_command`}}'",
+      "shutdown_command": "echo '{{user `ssh_password`}}' | sudo -S -E sh -c 'userdel -f -r {{user `ssh_username`}} && rm -f /etc/sudoers.d/{{user `ssh_username` }} && rm -f /etc/sudoers.d/90-cloud-init-users && {{user `shutdown_command`}}'",
       "ssh_handshake_attempts": "100",
       "ssh_password": "{{user `ssh_password`}}",
       "ssh_timeout": "2h",