Add dedicated variables for controlling Kakaotalk encryption

roles/matrix-bridge-appservice-kakaotalk/templates/config.yaml.j2

@@ -133,10 +133,10 @@ bridge:
     # application service.
     encryption:
         # Allow encryption, work in group chat rooms with e2ee enabled
-        allow: false
+        allow: {{ matrix_appservice_kakaotalk_bridge_encryption_allow | to_json }}
         # Default to encryption, force-enable encryption in all portals the bridge creates
         # This will cause the bridge bot to be in private chats for the encryption to work properly.
-        default: false
+        default: {{ matrix_appservice_kakaotalk_bridge_encryption_default| to_json }}
         # Options for automatic key sharing.
         key_sharing:
             # Enable key sharing? If enabled, key requests for rooms where users are in will be fulfilled.