prefix internal vars

tasks/config_default.yml

@@ -43,17 +43,16 @@
         owner: root
         group: root
         mode: 0600
-      register: sender_result
+      register: __sender_result
 
     - name: Ensure sender_canonical.db exist
       stat:
         path: /etc/postfix/sender_canonical.db
-      register: senderdb
+      register: __senderdb
 
     - name: Hash sender_canoncial
       command: "/usr/sbin/postmap hash:/etc/postfix/sender_canonical"
-      when: not senderdb.stat.exists or sender_result.changed
-      register: senderdb_update
+      when: not __senderdb.stat.exists or __sender_result.changed
       notify: __postfix_restart
   become: True
   become_user: root