Bug 1814322 follow-up - Fix test to account for bug 1814370. rs=me DONTBUILD

--HG--
extra : amend_source : 104f0d39e8028fc3f046fad36efcbcfe78ebb1e2

mail/base/test/browser/browser_fileMenu.js

@@ -47,7 +47,7 @@ const fileMenuData = {
   menu_settingsOffline: { disabled: true },
   menu_downloadFlagged: { disabled: true },
   menu_downloadSelected: { disabled: true },
-  printMenuItem: {},
+  printMenuItem: { disabled: ["mail3PaneTab"] },
   menu_FileQuitItem: {},
 };
 let helper = new MenuTestHelper("menu_File", fileMenuData);