fix: Fixed translations strings having a syntax error, b=no-bug, c=no-component

Author: mr-cheffy

locales/en-US/browser/browser/zen-general.ftl

@@ -124,7 +124,7 @@ zen-open-link-in-glance =
 
 zen-sidebar-notification-updated-heading = Update Complete!
 
-# See ZenSidebarNotification.mjs to see how these would be used
+# See ZenSidebarNotification.mjs to see how these would be used
 
 zen-sidebar-notification-updated-label = What's new in { -brand-short-name }
 zen-sidebar-notification-updated-tooltip =