fix: Add compatibility with CoreOS

vars/main.yml

@@ -0,0 +1,9 @@
+---
+# vars file for keepalived
+
+users:
+  - name: keepalived_script
+    comment: "Dedicated user for keepalived script"
+    update_password: on_create
+    password_lock: true
+    shell: /bin/bash