Revert "AccountsWindow: Fix back button"

This reverts commit 108b0878

gajim/gtk/accounts.py

@@ -82,10 +82,6 @@ class AccountsWindow(Gtk.ApplicationWindow):
         app.ged.register_event_handler(
             'our-show', ged.GUI2, self._nec_our_status)
 
-    @property
-    def stack(self):
-        return self._ui.stack
-
     def _nec_our_status(self, event):
         self.update_accounts()