Steps:

1. Run updater -> updates MaintenanceTool

• MaintenanceTool update confirmed, change in UI behavior
  2. Restart
  3. Run updater again to pick the rest of the updates
  4. Installation finished successfully. In the end of the verbose log
  the following can be found:

Warning: The current uninstaller/ maintenance tool could not be updated. '/home/iieklund/Qt532Test/.tempSDKMaintenanceTool' does not exist. Please fix the 'setInstallerBaseBinary(<temp_installer_base_binary_path>)' call in your script.

To summarize this error message was given for update operation which did not
include MaintenanceTool update. MaintenanceTool was updated already previously and that was successful.