Fix default_user syntax

cloud-init-fedora.cfg

@@ -46,7 +46,13 @@ cloud_final_modules:
  - final-message
 
 system_info:
-  default_user: ec2-user
+  default_user:
+    name: ec2-user
+    lock_passwd: true
+    gecos: EC2 user
+    groups: [wheel, adm]
+    sudo: ["ALL=(ALL) NOPASSWD:ALL"]
+    shell: /bin/bash
   distro: fedora
   paths:
     cloud_dir: /var/lib/cloud