Add close setting dialog hook

gui/gui_classic.py

@@ -2111,6 +2111,8 @@ class ElectrumWindow(QMainWindow):
             self.config.set_key('currency', cur_request, True)
             self.update_wallet()
 
+        self.run_hook('close_setting_dialog', (self,))
+
         if need_restart:
             QMessageBox.warning(self, _('Success'), _('Please restart Electrum to activate the new GUI settings'), _('OK'))