Fatal error: Uncaught Error: Undefined constant "STRIPE_SECRET_KEY" in /home/bounce28/public_html/time-tracker-backup/tests/test-billing-system.php:14 Stack trace: #0 /home/bounce28/public_html/time-tracker-backup/tests/test-billing-system.php(198): BillingSystemTest->__construct() #1 {main} thrown in /home/bounce28/public_html/time-tracker-backup/tests/test-billing-system.php on line 14