I’m encountering an issue while reopening my old project in CodeIgniter. When I run the spark command, I’m seeing the error message: ‘This “system/bootstrap.php” is no longer used. If you are seeing this error message, the upgrade is not complete. Please refer to the upgrade guide and complete the upgrade.’ Additionally, I’m getting a PHP Fatal error: ‘Undefined constant “ENVIRONMENT”‘. Could you please advise on how to resolve these issues?