[FIX] mail: fix translation issue in client notification

Closes #19095.

addons/mail/static/src/js/chat_manager.js

@@ -536,7 +536,7 @@ function on_partner_notification (data) {
             }
             remove_channel(channel);
             chat_manager.bus.trigger("unsubscribe_from_channel", data.id);
-            web_client.do_notify(_("Unsubscribed"), msg);
+            web_client.do_notify(_t("Unsubscribed"), msg);
         }
     } else if (data.type === 'toggle_star') {
         on_toggle_star_notification(data);